Technological Advancement in Mechanical and Automotive Engineering

Door hinges and latches are door retention mechanism elements that play an important role in automobiles by holding the door open in the event of a side impact or rollover collision. Hinges are a group of components that are attached to the vehicle’s door and frame, are related to one another, and can rotate along the same axis. Latches are mechanical devices that are used to position the door in a closed position relative to the vehicle body while allowing for controlled release. The standard specific conditions for side door latches and hinges installed on cars to reduce the risk of passengers being thrown out of the vehicle as a result of any impact. The objective of this paper is to identify the weakest point and to perform a structural analysis of automotive door hinge. Computer Aided Design (CAD) software is used to build a CAD model of the hinge and lock. The models of such components is meshed, and boundary conditions is defined, using the commercial meshing program. ANSYS is used to analyses the structural behaviour. Based on the results, the component will be further optimized for the future work.

The project represents graphene can be used as an alternative additive in the automotive cooling system. Thus, graphene nanofluids have been prepared at 0.1, 0.3 and 0.5% volume concentrations. Afterward, measurement of various thermophysical properties of nanofluid such as thermal conductivity, density, viscosity, and specific has been done. The obtaining data has been analyzed and compared with graphene oxide, titanium oxide, aluminium oxide, silicon carbide, and copper oxide nanofluid to figure out the best nanofluid that can absorb more heat to protect the car engine from overheating. In, summary, the overall best nanofluid among these six would be graphene oxide, with the best thermal conductivity, specific heat capacity, and one of the lowest viscosities. As for comparison among graphene all volume concentrations, the 0.1% graphene nanofluid demonstrated the best with high thermal conductivity and low viscosity.

Last two decades, the researcher is focused on increasing the braking torque of magnetorheological (MR) brake due to the insufficient braking torque to realize in commercial applications particularly vehicle application. Typical methods for enhancing braking torque include improving the rheological characteristics of the carrier fluid, modifying the structure of the MR brake, and raising the strength of the internal magnetic field. Although MR Fluid (MRF) is frequently used in MR brake as a carrier fluid due to its high responsiveness and ease of fabrication, the sedimentation problem has hindered the application of MRF in MR brakes. As a result, MR Grease (MRG) with high viscosity that reduces sedimentation is predicted to overcome the shortcomings of MRF through its unique self-sealing capabilities that efficiently solve the leakage problem. However, the torque performance of MRG is still low which hinder its performance in MR brake application. This review focuses on the usage of MRG instead MRF as a carrier fluid and the improvement of the MRG’s rheological properties which expected to improve the torque performance of MR brake. The factor influencing the rheological properties like the amount, size and shape of magnetic particles are discussed. Furthermore, a few potential additives have been used to improve the rheological properties of MRG and was expected can improved the torque performance of MRG in MR brake are also surveyed and discussed. Therefore, this review will be of significance to MR brake researchers who want to develop a high torque MR brake without occurrence of the sedimentation and leakage.

Based on research and sufficient evidence, the International Agency for Research on Cancer (IARC), which is part of the World Health Organization (WHO), classified exhaust gas from diesel engines as carcinogenic to humans (Group 1), which has been a factor in the worldwide increase in cancer lung cases. According to the preceding remark, this will become an issue for all diesel transportation, from the smallest, such as a generator used in a night market, to the largest, such as trains. To address this issue, many researchers and scientists study the diesel engine in order to ensure that this internal combustion engine improves in terms of emissions while maintaining performance and fuel efficiency. The diesel engine is known as a combustion that has a thermal efficiency of more than 45%. The most recent technique to reducing gas emissions from diesel engines is to modify the injection system to use dual-fuel Reactivity Control Compression Ignition (RCCI) with main reference fuel (PRF). The study on the RCCI technique shows that it can achieve low NOx and CO2 emissions while retaining the high performance of a diesel engine. To minimise HC and CO emissions, the future proposal for this method is to regulate the combustion phasing by regulating the injection at the port injector.

Reactivity-Controlled Compression Ignition or also known as RCCI mode engine is a modified of Homogeneous Charge Compression Ignition (HCCI) engine in which have a better control in combustion and wider load range. The strategies of RCCI mode in controlling the combustion is by using dual fuel of different reactivity such as diesel (high reactivity fuel) and gasoline (low reactivity fuel). The objective of this experimental investigation is to evaluate the effect of Primary Reference Fuel towards the emission produce by the RCCI engine mode. Single cylinder CI engine with port injection system is used in this study. Two alkane-based, iso-octane and n-heptane were blend together, PRF80 (80% iso-octane + 20% n-heptane) fuel mixtures were used throughout this study as low reactivity fuel in port injection system and pure diesel as high reactivity fuel in direct injection system. Result found that the performance of RCCI mode engine improve with the use of alkane (iso-octane and n-heptane) in the PRF80 blends especially in comparison to normal mode CI engine (using diesel only). In terms of emission, by using PRF80 in RCCI mode engine, the NOx reduce almost 95% of normal CI engine NOx production. As a result of applying PRF as a low reactivity fuel in an RCCI engine system, knocking resistance may be produced even at high engine compression ratios, resulting in better thermal efficiency and reduced NOx-Soot emissions.

Experimental work has been done to investigate emissions characteristics of a single cylinder diesel engine with the rice bran oil (RBO) diesel fuel mixture at various engine speed. The emission parameters evaluated were nitrogen oxide (NOx, carbon dioxide (CO2), hydrocarbon (HC) and carbon monoxide (CO). The results with rice bran oil based experiment, (RBO50, RBO75, RBO100) are compared with diesel (RBO00). The results exhibited that CO, CO2, HC and NOx emissions are lesser than diesel fuel; Hydrocarbon emissions for both RBO75 and RBO100 were observed at two engine speed (3500 rpm and 2000 rpm). Hydrocarbon emission for RBO75 were highest at 3500 rpm engine speed which is 211 ppm. RBO50 have less and better carbon monoxide (1.2% and 0.32% at 3500 rpm and 2000 rpm respectively) and carbon dioxide emissions (8.3% and 6.9% at 3500 rpm and 2000 rpm respectively) compared with diesel (RBO00) and other fuels mix at both engine speed; 75% load. Higher NOx emissions in diesel (RBO00) was observed which is 499 ppm and 599 ppm at engine 3500 rpm and 2000 rpm respectively as compared to other fuels; RBO50, RBO75, RBO100. In a nutshell, emission characteristics for rice bran oil were improved compared to diesel and RBO50 can consider as optimum mixture blend in terms of CO2, CO, NOX and HC.

Stirling engine categorized as external combustion engine which defined as a closed-cycle regenerative heat engine to perform the conversion of energy into the mechanical power. The thermal efficiency of the Stirling cycle always is the main criterion, and the literature showed its efficiency of energy conversion is consider relatively as high as the Carnot cycle. Although the Stirling engine consists of great versatility for energy sources, however still inadequate efforts were done for the development of the Stirling engine that is powered by combustion fuel, since generally the engine is fueled by renewable energy which is inapplicable by the public. Therefore, the objectives to fill up the research gaps are to simulate the operation condition of Beta type Stirling engine by manipulated the use of different fuels with the assistant of MATLAB then compared with the outcome of a reference model to validate the outcome and to acquire the optimum performance of the engine, and any index that brings a reputation for the development of the Stirling engine. Compression ratio, and the temperature of the heater that affected by the specifications of Stirling engine design and effective volume of the heater, respectively act as the major element that manipulated the final power output. A higher compression ratio of 18 and power output of 315.88 Watts can be obtained with smaller clearance between the engine primary components, besides the heater temperature that achieves 855.75 K and thermal efficiency of 64.93% is affected by the usage of appropriate combustion fuel as gasoline and bigger effective volume of the heater.

The dual fuel swirl combustion of soy biodiesel and natural gas was investigated using a generic gas turbine combustor. Liquid fuel spray was generated using air-assisted atomiser with air-to-liquid ratio 2.50. An axial swirler with a vane angle of 45° was utilised to produce the swirling air flow at burner outlet. Liquid fuel spray was then blended with swirling air to form a flammable mixture and setup the flame. The flame colour of soy biodiesel/natural gas was mostly blue, similar to pure biodiesel. When compared to diesel, biodiesel/natural gas combustion reduced nitric oxide emissions by a factor of averaging 3. Empirical model for estimating NO emission was also proposed. Predicted results were closed to experimental data, denoted by R2 greater than 0.95. This study demonstrates that biodiesel/natural gas combustion with a 20–30% natural gas input power fraction is a promising way to reduce toxic emission, offering a tactical approach to minimise hazardous emissions from neat biodiesel swirl combustion.

This article will aim to replace rubber in engine mounts with alternative materials, preferably composites. The engine mount is the most important component of a vehicle's engine; its job is to isolate and absorb engine vibrations. As a result, the engine mount is subjected to high stresses and adverse conditions. For example, high temperatures, chemical leaks, vibrations, and the engine's mechanical torque. Rubber has a lower life duration when all aspects are considered. As a result, many researchers have tried to extend the mount's lifespan. The purpose of this paper is to demonstrate this. To extend the mount's life and increase performance by decreasing power dissipation without sacrificing comfort, a combination of creative ideas and materials are combined. As a result, expect a stiffer and more durable mount. Three different materials are used to compare three different conceptual designs. Rubber, Polyurethane, and Carbon Fiber-Epoxy Resins are utilized in the Pugh technique to identify the optimal mix of conceptual ideas and materials. To identify the final combination, many analyses are performed, including structural analysis, random vibration analysis, explicit analysis, static deflection, and mount weight (Design 2 with CF-EP). Despite the fact that PU and CF-EP are equivalent, CF-EP warrants further investigation and testing because there is still room for development.

Plastic have now become essential materials in the present world and implimentation in the industrial field is persistently rising. The aim of this project is to investigate the effects of waste plastic oil on engine performance and pollutant emissions. The engine test was conducted under constant engine speed of 1800 RPM and varies engine load of 20%, 40% and 60% respectively. The performances of engine were analyzed in term of brake power (BP), brake specific fuel consumption (BSFC) and brake thermal efficiency (BTE). The effect of WPO on brake power was only dominant during low and medium engine load condition. WPO can reduce the BSFC of diesel engine except for high load condition. In addition, the formation of NOx and CO for WPO fuel blends were greater than D100 under all engine load conditions. Therefore, in conclusion, the implementation of WPO in diesel engine can improve engine performance but limit its effectiveness in terms of pollutant emissions.

Biofuel are commonly regarded as sustainable renewable fuels and are offers a feasible solution for social and economic development. Within the biofuel source, macroalgae are quickly becoming a typical contender as a possible third-generation fuel source due to ease of cultivation and fast growth rates. It is the most excellent bioenergy alternative that overcomes the downsides of first- and second-generation biofuels. Macroalgae based biocrude oil through Hydrothermal liquefaction (HTL) is a promising pathway for sustainable biofuel production. This study aims to compare the biochemical composition of 15 different species collected from various literature sources. The biocrude potential from different species are estimated and compared. The results suggested that green seaweed U. luctuca (16.81%) contain the highest percentage of biocrude content. This indicates the macroalgae as a promising feedstock for biofuels, bio-chemicals and other bio-products.

One of the devices used to improve heat transfer in heat exchangers is the decaying swirl generator. When the inlet flow passes through this turbulator, a swirling flow is created, which thins the boundary layer on the tube wall and improves the flow's force convection. This paper numerically investigated a new design of a decaying swirl generator known as the guide-vane swirl generator (GVSG). The GVSG has a diameter of 15.5 mm and a length of 35 mm, and it is placed at L/D = 10 in a tube with a diameter of 16 mm and a length of L/D = 93.75. It has four vanes, each with a length of L/D = 1 and half of each twisted 180°. With a constant heat flux applied to the tube, the heat transfer enhancement was tested for Reynolds numbers ranging from 4583 to 35,000. Ansys Fluent was used throughout the simulation process. The friction factor obtained a maximum value of 4.06 at the highest Reynolds number tested. The Nusselt number achieved a maximum value of 1.23 at Reynolds number 20,000. As a result, the maximum thermal-hydraulic performance (THP) of GVSG inside the heated plain horizontal tube is 0.81 achieved at Reynolds number 35,000. Since THP was less than unity, it is clear that GVSG causes a greater deficit in pressure drop than they promote heat transfer. As a result, the geometry of the GVSG proposed in this paper, such as its length, diameter, vane length, and twist angle, need to be adjusted to improve the GVSG's THP.

In the present study, two types of polymers that is biopolymer derived from vegetable oils and High Density Polyethylene (HDPE) was blended together. Biopolymer are covers both biobased and biodegradable polymers while HDPE is thermoplastic polymer that is easily remoulded and recycled. This is an advantage to produce bio-based polymer that can remould and degrade by producing a new polymer blend. The blended polymer of HDPE with 30% of BP via melt mixing technique using Brabender (B) machine and a manually mixed (M) namely as HB and HM respectively was produced. The sample in the form of dumbbell shape from the Injection Moulding machine was then exposed to Ultraviolet (UV) irradiation at a constant temperature of 50 °C for 500, 1000, 2000 and 3000 h irradiation exposure. The FTIR spectroscopy was identified that both HB and HM have the same functional group of C-H group at 2915 cm−1 and 2848 cm−1as the main backbone of the polymer blended structure. For HB and HM, peaks at 1697–1714 cm−1 were contributed to the C=O group in the amide region. For CH3 bending the peaks were observed at 1472–1462 cm−1. In addition, the carbonyl Index (CI) was calculated. HB shows the highest CI for 1000H irradiation exposure while 500H for the lowest CI. The HM of 500H exposed upon UV shows the highest while 3000H shows the lowest value of CI. After UV irradiation the CI of HB and HM shows fluctuated trend due to degradation occurring under photo-oxidation circumstances is the chain scission accompanying with the cross-linking and the formation of the carbonyl group.

Zinc oxide nanoparticles have been prepared by the sol-gel method at different solvent (methanol (MeOH), ethanol (EtOh) and distilled water) and at different calcination temperatures (700 °C, 800 °C and 900 °C). The phase and microstructure of the prepared ZnO powder were investigated. ZnO powder were characterized by using XRD, EDX and FESEM. XRD analysis shows ZnO exhibited a hexagonal (wurtzite) structure with crystallite sizes 34.146 nm, 34.283 nm, and 34.523 nm and FESEM micrographs show that synthesized ZnO has a nanorod-like structure with an average particle size, 113.716 nm, 125.825 nm, and 141.725 nm for solvent methanol, ethanol and distilled water and calcination temperature of 700 °C, 800 °C and 700 °C respectively. The obtained ZnO nanoparticles are homogenous and consistent in size, corresponding to the XRD results that exhibit good crystallinity. EDX analysis shows pure ZnO with different solvents at 700 °C calcination temperatures. The surface of the ZnO also exhibits elements of O and Zn. This result has confirmed that the ZnO nanoparticles has high purity. Based on the analysis from the XRD and FESEM test, the best solvent with the best calcination temperature has been chosen, which is Methanol at 700 °C.

Shell and tube heat exchangers operated with nanofluids are extensively studied and applied in the industry due to the capabilities of nanofluids as a more efficient working fluid compared to commonly used fluid such as water and oil. In this study, the shell-and-tube heat exchanger is modelled and analyzed using ANSYS, where temperature difference and pressure drop of alumina in water (Al2O3-water) and titanium dioxide in water (TiO2-water) nanofluids for volumetric concentration from 0 to 2.5% were studied. The results were compared with the findings from existing research and journals. Al2O3-water nanofluid showed significantly higher heat transfer enhancement compared to TiO2-water nanofluid for volume concentration ranging from 1 to 2.5%. Al2O3-water nanofluid also showed a temperature difference percentage of 12% for 2.5% volume concentration, while TiO2-water nanofluid showed 9.15% of temperature difference at 2.5% volume concentration.

Lubricants are derived from biological or non-biological sources. However, the use of stand-alone lubricants lacked desirable tribological properties and had hit their performance limit. A frequent solution to this obstacle is introducing a few but effective additives in the base oil lubricants. These formulations significantly enhance the lubricants, especially in thermal properties, tribological characteristics, and anti-oxidation capability. Advancement in nanotechnology offers the potential to enhance the performance of the lubricant base oil using nanoparticles additives. Introducing lubricant base oils with nanoparticles is critical to improving lubricant characteristics, mainly resistance to wear and friction. Understanding the base oil lubricants commonly used with nanoparticles is vital as the initial guidance in solving these obstacles. Therefore, this review paper aimed to highlight the classification of lubricants base oils for nanolubricants applications. A good understanding of the base oil lubricants leads to the quickly discovering of novel nanolubricants formulations.

The experimental study evaluates the specific heat capacity of diversified mono and hybrid nanofluids. Specific heat is one of the most important attributes of mono and hybrid nanofluids for various heat and thermal applications. Herein, varied mono nanofluids such as CNC, Al2O3, and ZnO and only one hybrid nanofluid such as Al2O3/CNC have been studied to figure out their specific heat capacity. Standard test method applied to measure the specific heat of mono and hybrid nanofluids by using DSC. Mono nanofluids and hybrid nanofluids present some significant results of specific heat capacity and hybrid nanofluids show a maximum of 126% negativity than mono nanofluids. These experimental values would be a good aspect of the nanofluid applications.

Bionanohybrids have been extensively studied as the cornerstone of novel materials for manifold applications. This research aims to fabricate layer-by-layer bionanohybrids of chitosan nanoparticles cross-linked natural cellulose using sodium tripolyphosphate cross-linker (Ch-TPP-C) and ionic gelation method. Chitosan coating enhanced the multi-functionality of natural cellulose obtained from rice straw waste. In turn, the functional groups of the cellulose matrix offer exogenous groups for chitosan as a coating agent. The image of scanning electron microscopy (SEM) of Ch-TPP-C showed that the spherical-like chitosan nanoparticles covered the entangled cellulose well. The hydrodynamic size of 128.50 and 205.73 nm was found for chitosan nanoparticles and Ch-TPP-C, respectively. The hydrodynamic size of the samples slightly increased after one month of storage. The results from X-ray diffraction (XRD) and Fourier transforms infrared (FTIR) spectra showed the formation of Ch-TPP-C with multifunctional properties. Therefore, the incorporation of dual polysaccharides of natural cellulose matrix and chitosan coater was successful to synthesize the low-cost bionanohybrids potentially for anticancer drug delivery applications.

Pyrolysis is taken into account as the foremost promising thermochemical conversion technology for converting solid wastes into liquid fuels. The present work focused on producing liquid from PET plastic fuel with catalyst employment through the pyrolysis process. Moreover, it aims to differentiate quantitively and qualitatively the liquid yield's improvement concerning the catalyst employed in its benzoic acid content, high heating value, density, and fire and flashpoint. The product yields and compositions are also determined. The experiment takes place in a batch reactor with a heating range of 350–500 °C. The process that used Ca(OH)2 as a catalyst encompasses a maximum liquid yield of 70.6%. In terms of density, the oil produced from three catalysts’ employment has comparable value with the commercial light petroleum fuel in a range of 794–884 kg/m3. The pyrolysis with the Fe2O3 catalyst has the lowest flashpoint of 28.2 °C, while the zeolite and Ca(OH)2 catalytic process has the same flash point of 30 °C. Also, the Fe2O3 catalytic process has the highest fire point of 40.6 °C among the three catalysts. The pyrolysis with Ca(OH)2 catalyst had a maximum heating value of 9284.05 cal/g when Ca(OH)2 was used as a catalyst. The paper concludes with the addition of catalyst, namely zeolite, Ca(OH)2, and Fe2O3, into PET plastic in the pyrolysis process, increased oil yields, and improved its characteristics.

MIM is a technique that is often used because it allows the production of complicated components with sophisticated geometry and accurate shape. The primary aim of this paper is to determine the optimal injection moulding parameters for WC–Co cemented carbide with TaC acting as a grain growth inhibitor (GGI) by using the Design of Experiments—Taguchi method. A significant proportion of green components is required to obtain the most efficient green porosity. This study applies the Taguchi technique to optimise the green porosity of injection moulded components depending on injection moulding parameters. These parameters were taken into account: GGI percentage, injection temperature, injection pressure, and injection speed. An orthogonal array of L9 (34) experimental base design was chosen as an experimental setup, and the responses were analysed using Minitab version 18. It found that the best parameter combinations for porosity are GGI (0.4 wt%), injection temperature (145 °C), injection pressure (45%), and injection speed (35%). Consequently, by managing the optimum parameter configuration, the intended product’s best performance may be attained and maintained.

Computer-aided cooling curve analysis (CA-CCA) is a cost-saving and easy-to-use thermal analysis tool to identify the solidification characteristics of a material. This paper aims to present the relationship between cooling rate and solidification parameters of aluminum–silicon alloy before semisolid metal processing. An induction furnace was used to melt the as-prepared specimen by heating the respective graphite crucible to 680 ℃ and left it to be cooled and solidified under three different cooling rate conditions. A double thermocouple method was employed by placing one K-type thermocouple at the crucible center and another one near to the crucible wall. Both thermocouple sensors were connected to a data acquisition device, NI 9219 which was linked to a computer with DASYLab pre-installed inside for data logging, along with OriginPro 2019b for graphical representation. Low, intermediate, and high cooling rate conditions were achieved when the crucible was cooled with its top and bottom surface enclosed with Fiberfrax felt (1.0 ℃/s), at ambient temperature (1.3 ℃/s), and by a compressed air flow supplied from air compressor (1.9 ℃/s), respectively. The increase in cooling rate facilitates the nucleation rate and the growth of crystals within the alloy system and thus leads to a shorter solidification time with all the critical points highlighting the phase transition are shifted accordingly.

High-strength steels are now increasingly used in automotive structural applications owing to their resilience, crashworthiness, and ease of manufacturing. This paper reviews the application of high-strength steels for the automotive structure, describing the condition of the steel after been put in the car structures. Thereafter, the importance of advanced high strength boron steel is highlighted, and its weldability is discussed. Current issues related to welding and changes in microstructure are discussed. It is imperative that Boron steel is gaining widespread attention due to its good mechanical characteristic in car structures and its weldability remains a topic of significant research interest. Lastly, the important considerations are summarized.

In this study, numerical analysis software is used to model the behavior of Tin Slag Polymer Concrete (TSPC) Column under compression. Concrete damage plasticity (CDP) model approach is employed to describe the TSPC property in the finite element (FE) model. FE model is developed based on experimental work data conducted by previous researcher. FE modelling of the TSPC column is performed with purpose to present baseline data for future improvement of the modelling as well as to facilitate future parametric study. The reason is that TSPC is a new material and there was no available previous FE model reported in previous literature as references. The FE model was validated by comparing the simulation results and experimental data for TSPC column under compression. The results indicate that FE model has achieved compressive strength of 37.65 MPa compared with experimental data of 37.62 MPa indicating 0.08% deviation and almost similar location of failure mode. Stress–strain curve indicating that FE model is stiffer than experimental specimen. In conclusion, the stress–strain curve and failure modes for the FE model must be further improved by adjusting CDP parameter in FE model to be able to describe TSPC column specimen accurately. However, the parameters applied can be used as references for future modification on modelling of the TSPC column under compression.

Martensitic P91 steel is desirable for structural components operating at elevated temperatures. It is extensively used in nuclear power plant boilers, pipelines, reactor pressure vessels, and steam generators due to its high creep strength and corrosion resistance. Predicting the P91’s creep rupture life is critical for safe operation. Numerous creep laws have been developed throughout the years to anticipate the deformation, propagation of damage, and rupture of materials subjected to the creep phenomena. The Omega method is one of the most widely used in API RP579 on fitness-for-service purposes. In this study, the creep tests have been performed at 600 °C for 160, 180 and 190 MPa. In order to predict the rupture life, the omega method has been employed, which utilised the initial creep strain rate and creep strain. The experimental data has been compared to available literature data for P91 material. The predicted life was always more significant than the experimental result, and it was strongly linked to the omega value. The result shows that the value omega value of the test data are in line with the available data and the initial creep strain rate increased linearly with increased of stress and temperature. The predicted rupture life values are consistent and close to the experimental results.

This investigation inspects on the effect of cavity’s thickness during metal casting process on the corrosion resistance of copper alloy product. As the thickness increases, the cooling rate becomes higher due to higher latent heat available in the thicker and larger cavity volume. As such the quantity of Dendritic Arm Spacing, DAS and its Secondary, SDAS per unit area becomes higher. This eventually results in better properties such as the higher hardness and good corrosion resistance because its correlation with DAS and SDAS distribution in the microstructure. The copper alloy used in this project is Nickel Aluminium Bronze (NAB) alloy which consists of elements such as the copper, aluminium, iron, nickel and manganese. Sand casting process has been used and the NAB alloys have been fabricated according to the ASTM B148 UNS 95,800 standards with the usage of 1.1% degassing agent. A range of product cavity’s thickness have been fabricated for gating system and proper machining processes have been carried out to prepare the specimens for the immersion test. The specimens were immersed in sea water for a period of 17 weeks and changes in the specimen mass and pH and TDS values of the sea water used was measured. The data analysis revealed that the specimens were not corroded yet for the period of 17 weeks as there are not much changes in the specimen mass. The pH and TDS values are showing changes but these changes are very small comparatively.

A new generation of smart coating contain nano capsule that actively respond to changes in the local environment has triggered great interest among material researchers in the field of anti-corrosion. Many researchers reported that the preparation of pH-responsive nano capsules is usually applying unfriendly chemicals, a complex procedure and time-consuming, which remains as a great challenge for effective corrosion protections. This review presents, the achievement during the last 10 years in the field of pH-responsive nano-capsules, the formulation technique of such nano-capsule, testing and evaluation of the pH-responsive nano-capsule.

Magnesium (Mg) alloys with addition of strontium, such as AJ62, are die-castable and have good creep resistance at high temperatures. The formation of compounds containing strontium are extremely useful to increase the elevated temperature properties and strontium is an effective grain refiner for magnesium alloys. In this study, the effect of artificial aging of AJ62 magnesium alloys on the microstructure development and mechanical properties was studied. The alloys were solution heat treated, cooled to room temperature, before artificially aged to the room temperature. Different heating times and cooling conditions in the aging parameters were used. Aging time and cooling conditions affect the dendrite and eutectic phases refinement and lead to varying mechanical properties. Refinement of dendrite size enhanced the ductile properties.

AlSi10Mg alloy produced by additive manufacturing (AM) technology using direct metal laser sintering (DMLS) technique has resulted better in handling complex geometry. However, limited studies are performed for this AM method to show the integrity of aluminium alloys produced by DMLS to meet the required industry standard. This study investigates the effect of post-process on microstructure, mechanical properties, and fatigue life behaviour to AlSi10Mg material that DMLS produces. In this study, the specimens were tested with different post-process types: annealing (TS) and heat treatment processes (T5 and T6 conditions). All test results were compared with as-built processed specimens. Scanning electron microscope (SEM) and optical microscope are used to capture the microstructure images. The results showed that the tensile strength of the post-processed was decreased approximately 25% (decreased from 391 to 299 MPa). Still, the ductility was approximately 200% (in-creased from 3.2 to 6.8%) higher than the as-built specimen. This is because spherical silicon particles become coarsened when the specimen ductility is increased after heat treatment. For fatigue behaviour, it shows the as-built and heat-treated specimens are closely similar compared to findings from the literature. Overall, this study showed that the post-process changed the tensile strength and microstructural of AlSi10Mg but only significantly improved fatigue performance.

This study investigated the quenching performance of a copper rod with 50 mm length and diameter of 20 mm. The specimen was heated to 600 °C as the initial temperature and immersed in a quenching pool of pure water (distilled water) followed with a subsequent quench seven times. Under atmospheric pressure, the experiments are conducted in saturated and various subcooled conditions (90, 80 and 60 °C). The cooling curves (temperature vs time) and the cooling rate curves (°C/s) of the copper cylinder are obtained from the experiment. Results show that the cooling performance for 1st quench and the subsequent quench for saturated and 90 °C subcooled condition shows a different performance related to the formation of the oxide layer at the copper surface that changes the surface characteristic. Vice versa, the cooling performance in 80 °C and 60 °C subcooled conditions has consistent performance for all quench, which is believed to be the domination of the subcooling effect, even though the physical surface appearance shows the same. Overall, the cooling curve of the copper rod was enhanced with the increase of subcooled temperature, especially for 60 °C subcooled conditions. The cooling curves for the subcooled of 90 and 80 °C still maintain the slope with the three-section shape, which is similar for the saturated case, but for the 60 °C subcooled conditions, the cooling curve slope suddenly increased and shifted to the left, showing the drastic decrease of centre temperature and the impact on the highly subcooled condition. The cooling rate curve shows the increasing peak value of cooling rate with increasing the subcooled temperature, which is the highest value during quench in 60 °C conditions. The minimum heat flux (MHF) point temperature rises and occurs faster, and the Critical Heat Flux (CHF) point is achieved early with the increasing subcooled temperature. The highly subcooled condition 60 °C shows no film boiling regime formation and the MHF point location is not visible.

Subsea pipeline is prone to the damage due to fishing activities. Bottom trawling is one of the threats to the pipeline integrity. Fishermen used bottom trawling method to catch large volume of fish and benthic along the trawl route on the seabed. This causes the trawl net to be stuck on the subsea pipeline if their activity is close to the oil and gas platform. This paper evaluates the risk of subsea pipeline fish trawling operations on the east coast of offshore Peninsular Malaysia. On-site surveys were used to establish the characteristics of trawling devices used by local trawlers in the region. Based on site survey that was conducted, the frequency of fish trawlers crossing the pipelines is estimated. The pull-over load estimate for the otter board was determined using the Det Norske Veritas Germanischer Lloyd (DNVGL) algorithm. The severity and frequency index of the risk matrix was developed based on literature review. The findings showed that the pull-over load of otter board would not damage the pipelines. The risk presented to the pipelines by the operations of fish is considered low and moderate.

Zinc oxide nanoparticles (ZnO NPs) is a very attractive materials due to their favourable properties that can be applied in various applications. These desirable characteristics of ZnO NPs can be tailored based on the synthesis process. With the increasing focus towards environmentally friendly process, green synthesis has been gaining popularity as the preferable approach. This study focused on the ZnO NPs’ synthesis through sol–gel process in the presence biopolymer, pullulan. The impact of pullulan’s amount on the ZnO NPs’ characteristics were studied. Based on the results obtained, the general trend observed was that the particles size decreased with increasing pullulan amount. The determined band gap of ZnO NPs was found to be approximately between 3.26 and 3.28 eV. Overall, these results indicate that the properties of ZnO NPs is dependent on pullulan amount. These green synthesized ZnO NPs can be applied across various fields such as pharmaceuticals, cosmeceuticals, environmental and others.

Thruster performances can be optimized by adjusting the geometrical configurations and its operating conditions. Attributes such as pressure loss across catalyst bed, mass flowrate, and velocity are essential parameter to its performance. The presence of silver catalyst as porous medium affecting the flow and reaction inside the chamber due to its properties such as porosity, permeability, and inertial resistance. Hence, this work is motivated by the scarcity of the available literature on this topic specifically in regards with the hydrogen peroxide monopropellant thruster. The effect and relationship of porosity and permeability characteristics on the silver catalyst to the thruster performances is yet unknown. To investigate the effect and also to find the relationship between thruster performances and porosity—permeability properties of a silver catalyst, a study is done using Computational Fluid Dynamics (CFD). In this study, species transport model with EDM turbulent-chemical interaction has been used with the realizable k-ε turbulent to simulate the reaction inside the catalyst bed chamber. Extensive analysis provided in the current work which considers the performances in term of mass flowrate, velocity, pressure loss, and thrust. From this study, it shows that the porosity of the bed is least important compared to the permeability and inertial resistance of the silver catalyst and these two factors are independent from the effect of porosity but linked between one another.

The multi-stage pressure reducing valves are increasingly used in technical engineering fields such as residual oil hydrogenation. The overall performance of the valve can be affected by a numbers of factors, and the effect of roughness is still not fully understood. Using computational fluid dynamics technology, the influence of roughness on the throttle characteristics of the spool of a series multi-stage pressure-reducing regulating valve is studied. Under the same inlet velocity condition, numerical simulation of different roughness is carried out, and its influence on the internal flow of the series multi-stage pressure reducing valve is analyzed. The findings depict that the maximum pressure difference in the valve and the friction pressure difference increase with the increase of the roughness and after 2 mm, the increase decreases with the increase of the relative roughness, and finally gradually stabilizes; the average velocity at the valve outlet and the average internal velocity decrease progressively with the increase of roughness, and the relationship is approximately linear; at the roughness of 1 mm, the maximum wall shear stress is 5.6 times that when the roughness is 0 mm. In addition, the flow resistance coefficient increases linearly with the increase of roughness. The research results can provide theoretical support for the structural design of the series multi-stage pressure reducing valve.

Using potentiodynamic polarization, AC impedance and Mott-Schottky curve measurement methods, the electrochemical behavior and passivation characteristics of 316L stainless steel in 3.5% NaCl solution were studied. The experimental research results show that: The passivation film on the sample surface is relatively stable in the low-temperature alkaline solution. As the temperature of the solution increases and the pH decreases, the pitting potential of 316L stainless steel decreases accordingly, the corrosion current density increases, and the passivation interval decreases; The donor concentration and acceptor concentration near the surface oxide film increase; The change trend of electrochemical impedance spectroscopy is obviously different, and the pitting corrosion resistance of stainless steel becomes worse.

Coal chemical industry transportation of coal slurry is a typical solid–liquid two-phase flow, this process is accompanied by the erosion and abrasion of the pulverized coal slag on the inner wall of the pipeline. This phenomenon will have a significant impact on the service life of the transportation components and become a hidden engineering hazard. Aiming at the erosion problem of the coal chemical transportation system, the variable diameter pipe in the commonly used pipeline in this working condition is taken as the research object, based on the actual working condition, using the discrete phase model, track and solve the particle motion trajectory information under the Lagrange framework to obtain particle motion information. And combining this information with the erosion model, the effect of the particle size of the cinder and coal powder on the erosion of the inner wall of the pipeline is analyzed. The results show that as the particle size increases, the maximum erosion wear rate decreases. When the particle size is less than 500 μm, the maximum erosion wear rate decreases faster, when the particle size is greater than 500 μm, the maximum erosion wear volume decreases slowly. This study can provide a certain theoretical basis for the design of coal chemical transportation pipelines and the research on erosion, wear and maintenance.

The research on the mechanism of nozzle baffle at home and abroad mainly focuses on the theoretical research of nozzle baffle gap and back pressure, and lacks engineering application. This paper takes the remote pressure maintaining system of shield machine as the research object. Aiming at the problem of baffle inclination caused by impurities in the nozzle baffle mechanism during shield machine construction and maintenance, a simulation experiment was carried out on the nozzle baffle mechanism. Draw the characteristic curve of nozzle baffle clearance and back pressure; The relationship between baffle angle and back pressure under different nozzle baffle clearance in engineering practice is analyzed; The linear regression model is established to prove that the problem of shield remote pressure maintaining system is not caused by the inclination of baffle, which provides a theoretical basis for the maintenance of shield remote pressure maintaining system.

A two-degree-of-freedom seven-bar three-axis fixed composite mechanism was introduced. The mechanism was divided into two closed loops to provide the position and direction of movement for the end effector components. Two four-bar analytic equations were constructed through complex number operations, the closed kinematics equations of the mechanism were established, and then converted into a matrix format. The Jacobian matrix was further deduced, and the geometrical analysis and solution of the mechanism model were carried out, and the mathematical model was analyzed. The Jacobian matrix was used to establish a mathematical model, derive the working space range of the mechanism, establish a kinematics model, and obtain the end-effector position, speed and acceleration curve graph. The purpose was to accurately calculate the energy parameters of the mechanism at work. The simulation results showed that when the end-effector moved to the lowest position, the speed was zero, the acceleration change was small, and the impact was minimal. The corrugated cardboard box flap can be folded to the horizontal direction without causing damage to the surface of the box. The correctness and feasibility of the mathematical model was verified by energy parameters, which provided the basic principle analysis for the organization and provided a theoretical reference for practical applications.

Energy saving is one of the challenges of today. In recent years, growing concerns about the environmental impacts of energy consumption and global warming has doubled the importance of this issue. This study has outlined five energy saving actions as proposed to decrease the office building energy consumption. The proposed energy saving actions was identified as reducing lamps number, changing the lamps specification, installing the lamps sensor switch, controlling the setting of air conditioner temperature and applying the sustainable energy management system. The KWSP building in Kedah, Malaysia, was the target office building and the energy audit was conducted in a specific area of the building. The proposed energy saving actions was analyzed by comparing the result of the payback period (PP) and the net present value (NPV) method where the main goal is to select which energy saving actions resulted more economically helpful. The economic analysis was conducted for each of the proposed actions and the result shows that the most profitable investment in terms of the PP is Action 4 or Action 5, Action 1, Action 2 and Action 3. For the NPV analysis, the sequence has been slightly changing with Action 4, Action 5, Action 1, Action 3 and Action 2. In overall, all the energy saving action is suitable to be implemented in an office building as the initial investment can be recovered in less than 2 years.

The hybrid generator is one of the renewable energy projects that is supposed to alleviate the issue of electricity availability and cost. It can be regarded as a green technology because the solenoid's magnetic induction is the system's primary source of electricity generation. Unlike a diesel generator, it generates power by burning diesel fuel and emitting CO2 into the atmosphere. Other forms of generators, such as solar and wind turbines, have efficiencies that are affected by weather and season. A hybrid generator system produces electricity by turning magnetic induction force into mechanical energy, which is subsequently converted back into electrical energy by the generator. Simulating a combined magnet solenoid to show how the system reacts when magnetic flux from the solenoid exists is part of developing the hybrid generator prototype. To generate power, this prototype uses translation motion that is subsequently transferred to rotational motion. The prototype's design will serve as a guide for developing the system during the fabrication process. Furthermore, while replacing their energy source with a magnet and solenoid, the existing generators concept is referenced to. The solenoid will serve as an energy source, generating mechanical energy and transferring it to the generator via a crankshaft for conversion into electrical energy. The current prototype of a hybrid generator can be improved to boost its capabilities and efficiency in order to generate more electricity. The relevance of this research is to present new alternate energy that is superior and can solve the problem of generating power using the existing generator.

Present day, insufficiency of energy supply is a major concern around the world. Many renewable energy sources are been in used to overcome this problem. Hydropower is one of the most reliable and sustainable energy sources that can generate electricity. Nowadays, pico hydropower are getting more attention than conventional large hydropower plants due to the high expenditure and environmental concerns. Pico hydropower is an alternative solution that offer low cost and high efficient. Due to its cost-effective factor, pico hydropower turbines can be best introduced to remote areas with insufficient electricity power supply like rural areas in Sabah and Sarawak. The purpose of this study is to design and testing a pico hydro turbine. A prototype model for the design concept of the pico hydro turbine with simpler mechanisms has been developed and tested. The prototype is able to generate power approximately to 11.3 V from the performance testing. The overall highest efficiency of the pico hydro turbine based on the test results is 90.45% at 9.84L/min water flow rate. Thus, this prototype can provide enough power to power LED light bulbs and table fan. The tests results find that the design concept of the pico hydro turbine can become a mini electricity generator.

In the last decade, coupled convection and radiative engineering problems has emerged as a major area of study in the engineering applications and sciences. The present paper deals with a transient (steady and unsteady) combination between free convection and volumetric radiation in a closed enclosure in thermal incompressible fluid flows in a bi-dimensional, differentially heated enclosure with emitting, scattering and absorbing volume. In the equation of energy, the radiative heat flux was simulated using the CVFEM, (Control- Volume-Finite-Element-Method) in the RTE (Radiative Transfer Equation). The Navier–Stokes equations which describe natural convection were solved with a D2Q9 temperature and velocity flow distributions using Lattice Boltzmann BGK Method. Separate particle distribution functions in the LBM were used to calculate the density, velocity and thermal fields. The obtained findings in the current work were compared with literature and good validation are demonstrated. The streamlines, the horizontal and vertical velocities, midline temperature, and the isotherms were highlighted and discussed under various parameters such as Rayleigh number, convection radiation number, in both steady and also unsteady cases. The LBM-CVFEM was ascertained to be a reliable numerical technique for future engineering applications dealing with transient coupling heat transfer problems.

Magneto-Hydro-Dynamic associate to convection heat transfer mode in a two-dimensional cavity filled with conducting fluid having a partially open-ended wall, is discussed in the present work. This engineering application is crucial to understand dynamic and thermal behavior of flow in frequent conclusive practicable and industrial applications in renewable and sustainable energy fields, specifically in collectors based on solar energy. However, scare open literature is find dealing with this important subject. Simulation of this coupled complex engineering physical problems in Magneto-Hydrodynamic (MHD) configurations is a great challenge for traditional CFD numerical approaches. In this paper, we apply the lattice Boltzmann method (LBM) in order to resolve a given engineering numerical simulation struggle. Knowing that, LBM is becoming in the last decades, an essential attractive tool for existing CFD approaches aiming to resolve complex numerous fluid flow problems with complex numerous difficulties. We intend in this work to afford a short review of researches dealing with application involving MHD convective simulations based on LBM aiming to predict the dynamic and thermal behavior recognizing more openings horizon for coming research. In addition, novel findings were highlighted within this work. First, the proposed Lattice Boltzmann model is validated and good agreement is found. Using an in-house LBM code, we introduce the effect of the Rayleigh number, Prandtl number, Hartmann number and geometrically, the position of the partially open-ended wall side in the MHD enclosure. Parametric findings show that all the coefficients influence significantly flow field and also temperature field patterns. This paper provides very useful beginnings for the applicable future MHD convective engineering studies.

The paper reviews the Microwave Hybrid Heating (MHH) method as well as the effect of MHH towards the interfacial reaction and the shear strength at the solder/Cu joint. Previously, reflow soldering process was performed to solder electronic component. Due to its high defect rate, processing time and energy consumption, MHH method are getting more attention among electronics manufacturers to perform industrial process as it is beneficial in modern microtechnology. MHH method has faster heating rate, improve heating uniformity, reduces the chance of thermal runaway, reduce processing temperature, and reduce hazards to human and environment. This approach has proven to yield scallop-like and angular trapezoid structure of Cu6Sn5 and Cu3Sn in the intermetallic compound (IMC). The IMC thickness shows a competitive result (5.337 and 5.717 μm) compared to reflow soldering. However, not many studies were done on the shear strength of the solder joint.

As the world marches forward implementing concepts of sustainable buildings, higher reliance on natural ventilation can be obtained through louvers. In this research of cross ventilation in a generic isolated building, the leeward opening sizes were manipulated to 1:1, 1:0.25 and 1:0.5, with louver angles of 0°, 15°, 30°, 45° and no louvers. An Atmospheric Boundary Layer (ABL) condition was applied at the inlet of the flow domain and a 3D-steady Reynolds-Averaged Navier–Stokes (RANS) equation was solved with the Shear Stress Transport (SST) k-ω turbulence model. Mesh sensitivity analysis and model validation were performed as per best practices. The results show that as the size of the leeward opening decreases, the acceleration through the louver blades increases. In the absence and presence of louvers, as the windward-louver (W-L) ratio increased from 1:0.25 to 1:1, its dimensionless flow rate (DFR) increases. Highest DFR was obtained when the W-L ratio was 1:1 and the louver angle was 0°, second to louver angle of 15°, followed by the configuration without louvers present. Their respective DFR values were 0.588, 0.544 and 0.522. As the louver angle increased from 0° to 45°, the DFR reduced for all opening W-L ratios.

The study presents the usage behavior of graphene in the energy field. Graphene has been comprehensively studied in the energy-related application due to higher conductivity and mechanical flexibility. The architecture of graphene permits it to strengthen and facilitate its application in the energy arena. Herein, the application of graphene in various energy storages such as fuel cells, dye-sensitized solar cells, batteries, nuclear power plants, and thermoelectric has been studied neatly. Graphene reacts towards these substances chemically, mechanically, and electrically to a great extend and appears with the excellent output of these objects. In the future graphene could be applied to the others field of energy and science successfully.

In the previous work, fabricated smoke wire technique in an atmospheric boundary layer wind tunnel displayed several flaws during experiment such as manual-dripped solution, leaking problem, utilisation of single heated wire, and an ineffective wire heating system in which the electrical circuit did not operated with desired optimum output to heat the wire efficiently. Therefore, present study fabricates an improved smoke wire technique with a control dripping valve to control the dripped-liquid solution quantity and frequency and aims to perform a qualitative investigation to visualize the flow pattern around a simple two-dimensional rigid body namely rectangular and cylinder. The experiment was conducted in a shorter test section of the quasi-atmospheric boundary layer wind tunnel. The wind tunnel has a working section of 0.3 m height and 0.3 m width with a streamwise length of 1 m. The enhanced fabrication successfully produced a continuous and high-quality smoke lines which utilised 10 lines of nichrome wires in a series circuit compared to a single wire in the previous work. The smoke visualization for the combination of 0.4 mm nichrome wire (type C) with 0.6 mm nozzle size at 25.98 V (3.5 A) was found to be the best condition for a continuous smoke streamline. As a result, from the two-dimensional flow experiment past rigid body, a pair of tip vortex structures, horseshoe vortex, and the downwash flow can be evidently seen.

Heat transfer performance of heat exchanger system play significant role toward energy conservation. In this research, numerical simulation using ANSYS was conducted to evaluate the performance of square twisted tube and oval twisted tube for heat transfer enhancement. A comparative models were developed to evaluate the geometry alternation on heat transfer coefficient and pressure drop. The analysis revealed that the square twisted tube heat exchanger has better performance and smaller friction factor compared to the oval twisted tube heat exchanger. Moreover, a computational fluid dynamics (CFD) simulation with a realizable k-ε was used to investigate the influence of twist pitch length on the heat transfer performance and pressure drop. The geometrical parameters include two different cross-section shapes and two different twist pitch lengths of the square twisted tube heat exchanger. The twist pitch lengths used in the investigation are 160 mm and 200 mm. The numerical results shown that the tube with the smallest pitch length offers a higher friction factor and Nusselt number. In addition, heat transfer mechanism of twisted tubes, velocity, streamlines, Nusselt number distribution, and temperature distribution are presented. Heat transfer enhancement of the square twisted tube heat exchanger is associated with the secondary flow production by the curved tube wall. In the oval and square twisted tubes, a secondary flow is formed which offers a longer flow path, hence an enhanced heat exchanger performance. It concluded that alternation of geometry on tube surface is potential to improve the overall performance with acceptable pressure drop.

Chiller system is one of the main components of the HVAC system and can be cooled by water or air. The core components of vapor compression chiller systems are compressors, condensers, expansion systems and evaporators. The type of evaporator usually used in the HVAC chiller system is a shell and tube evaporator. Hence, this project aimed to study the effects of industrial standard tube arrangements which are triangular (30°), rotated triangular (60°), square (90°) and rotated square (45°) on the heat transfer performance of evaporator chiller system and selecting optimized tube arrangement design. The methods were used are designing of the four geometries of the shell and tube evaporator and the ANSYS Fluent for the simulation of the designs. The boundary condition of this study was, the inlet mass flow rate of the cold fluid (Refrigerant 134a) was 2.5 kg/s, whereas the mass flow rate of hot fluid (water) was 3.3 kg/s. Also, the hot fluid temperature at the inlet was 12.2 °C and the cold fluid inlet temperature was kept at −15 °C. Based on the study findings, the shell and tube evaporator with tube arrangement at 45° transfer more heat transfer than the other three designs in the CFD. The shell and tube evaporator at tube arrangement 30° was chosen to be the optimized design based on the overall performance. Thus, this study will benefit the HVAC chiller system evaporators. Thus, this study will benefit the HVAC chiller system evaporators.

The effect of air filter pressure and fuel consumption for gas turbine generating Block 1 in the Southern Power Generation (SPG) power plant is presented. The prime mover for the generating block is the GE 9HA.02 gas turbine, and the power plant is the latest combined cycle gas turbine (CCGT) commissioned in January 2021 and the world’s first commercial operation of the GE 9HA.02 fleet globally. Fuel consumption of the gas turbine is the primary concern as it which significantly affected by the gas turbine performance, which later translates to the power plant revenue to operate at optimum cost. Note that the fuel consumption of the CCGT is closely related to the Air Filter House (AFH) condition located at the most upstream component to protect the gas turbine from erosion, corrosion and fouling; as well as to achieve the required performance, efficiency, and life expectations. The present work aims to evaluate the value of pressure drop in the AFH and the fuel consumption. These two related parameters are significant for mitigation measures to achieve a cost-effective power plant operation. The operation data for both parameters based on the actual CCGT plant operation has been analysed from March to June 2021. Consecutively over the four months of operation, the AFH pressure drop had increased from 666.80 to 741.12 Pa (Pascal), translating to a total increment of 74.32 Pa or an average of 18.58 Pa every month. Separately, fuel consumption increased from 120,460.61 to 123,614.13 m3/h, a total increment of 3153.52 m3/h or an average of 788.38 m3/h for every month, which later translated to an average increment of fuel cost amounting to RM 767.86/h. The present results reveal that the AFH pressure drop has directly impacted the fuel consumption over the analysis period. On average, an increment of 1 Pa of the AFH pressure drop will increase fuel cost amounting to RM 41.33/h. It is expected that current air filtration elements can last within 41 months to achieve their allowable pressure limit but are subjected to environmental and operating philosophy changes. The analysis results could be the basis for early filter replacement, proper selection of filter elements and frequent conduct of online and offline compressor washing as recommended by the manufacturer.

District cooling system (DCS) is a popular cooling solution for many institutional applications in Malaysia due to the energy-saving advantages as compared to traditional individual on-site cooling production. However, the problem with DCS is that it’s designed on fixed parameters automation prior to its commissioning and system performance is inefficient by the inability to adapt to uncertainties during operation. Objective of this DCS study is to propose a feedback control algorithm to be implemented in a DCS in Malaysia, as well as assess the proposed algorithm for further improvement. A case study of an existing DCS in Tronoh, Perak is performed in MatLab Simulink. The existing algorithm and the proposed algorithm of improved scheduling are implemented, and the simulation results have compared. The motivation of the new algorithm developed is to see further energy-reduction optimization, especially at the TES charging hours at low demand. The simulation results show improvements in the system efficiency of increased 22.6% (weekdays) and 48.2% (weekends) with reduced overall cooling output, and system energy savings of between 18.7% (~17 MWh at weekdays) and 32.1% (~21 MWh at weekends). Simulated model compared with historical data shows that the simulation model cannot replicate the exact conditions and output values of the actual DCS, but the trend of the output data is sufficiently accurate to model the improvements of implementing feedback control.

The excessive energy consumption through the last decades especially from the air conditioning due to the negative awareness behaviour of consumers has reflected not only on the economy but also on the weather and environment. The aim of this study is to save the energy inside the buildings by applying potential thermal insulation to reduce the usage of the air conditioning and save the cost of the electricity bill. Thermal insulation has been used in this study is Polyethylene Bubble Aluminium (SB250-FR+ with 4 mm) on the roof of the guardhouse of UCSI University to reduce the cooling load inside the buildings. The devices that have been used in this study are TSI VELOCICALC to measure the air temperature and air velocity, with Infrared Thermometer to measure profile temperature of the walls, windows, and roof. The data have been collected for 30 days from 9 am–5 pm with and without insulation. The data present shows, the insulation has helped to reduce the load inside the guardhouse. The results show that the heat inside the room has been reduced by is 26.6% and this could help to reduce the usage of the air-condition unit inside the room and save monthly around RM 80. The potential insulation has approved to save the energy inside the buildings that will help to reduce the heat tension of the occupants.

Reducing fine particles emission from wood waste fuel-driven boilers is one of the most challenging problems associated with exhaust pollution control. Cyclone separator (CS) is the most popular and cheaper air pollution control equipment. But it has limitations for fine particles (PM2.5). This research aims to improve the design of CS and evaluate its performance for the effective control of fine particles. An aggregation chamber (AC) installed at the entrance of CS can enhance the system’s performance. Mixing mists and flue gases in the AC resulted in the build-up and growth of clusters with sizes that can be easily captured in CS by inertial methods. Samples were collected over three different flue gas velocities from three sampling port locations in the AC. The experimental research was performed to explore the performance of CS modified with an AC. A total of 28 experiments were conducted. Results were all investigated using Scanning Electron Microscopy and Energy Dispersive X-ray spectroscopy (SEM–EDX). The study proved the effectiveness of AC in enhancing fine particles to 242 μm at 24.4 m/s flue gas velocity for concurrent flow. Fine particles that could have been emitted to the atmosphere were reduced by 82.3%. Thus, collection efficiency was significantly improved with the installation of AC at the entrance of CS.

The use of vapor compression air conditioning has contributed to the global warming effect by increasing greenhouse gas emissions. Renewable energy from geothermal sources, specifically ground heat exchangers (GHE), has great potential in building applications. The underlying concept of pipe called GHE utilises the ground as an unlimited thermal reservoir for cooling and heating purposes. Because of the temperature differences between underground and surrounding air, the air in the underground cools in the summer and warms in the winter. Thermal conductivity of the ground or soil is among a parameter that contribute to the GHE’s performance. Therefore, the purpose of this research is to investigate the effect of hybrid soils without moisture on the performance of the GHE system. The hybrid soils consist of two elements, which are native soil with three grain sizes and bentonite. The native soil grain sizes are 0.154–0355 mm, 0.355–0.6 mm, and 0.6–1 mm. Bentonite has been introduced into all native soil grain sizes, which ranges from 0 to 100%. The native soil and bentonite were mixed consistently, and the thermal conductivity was measured by using a thermal property analyzer device. The study shows that the grain size 0.6–1 mm of native soil has the highest thermal conductivity at 20% bentonite, which is 0.269 W/m K compared to other grain sizes. The performance of the GHE system was evaluated based on simulation of mathematical model which shows that pipe length of 16 m gives significant effect of temperature reduction. In short, the performance of GHE has increased once the thermal conductivity of hybrid soil increased.

Boiler efficiency could be analyzed using two different methods, direct and indirect. The direct method provides the overall efficiency based on input and output while indirect method shows the losses in each process which is more valuable in identify the inefficient process. Therefore, in this study, the effect of different boiler load on the efficiency of the boiler is analyzed using both methods. In addition, the analysis using indirect method also shows the effect of boiler load on the losses in dry flue gas and moisture in air. Data of the temperature, pressure and flow rate of the steam, flue gas, air and fuel are measured onsite. The flue gas analysis was performed to obtain the percentage of flue gas components. Direct efficiency and indirect efficiency based on heat losses at different points were calculated. From the study, it is found that, the efficiency of the boiler increased with the increment of boiler load and reach the maximum efficiency of 83.3% for direct method and 89.8% for indirect method at 55% load. Operating above 55% load will results in the decrement of boiler efficiency for both direct and indirect method. As the load increase, the amount of excess air is increasing which increase the combustion efficiency. However, as the excess air quantity increased further, the heat loss due to the excess air is higher than the heat input by the combustion therefore decreased the efficiency of the boiler. This result could give a clue to the boiler operator to tune the excess air rate when operating the boiler more than 55% load.

The sunlight has traditionally been the primary source of daylight. However, the advent of modernization has made people highly dependent on artificial lights. The technological development in the field of electric fixtures, dimming technologies, electronic ballasts, and light sources has nearly replaced the requirement of natural light in a room. This is not only harmful to the environment because of huge energy consumption but also harms human health. The social infrastructures such as hospitals, banks, institutions, multi-level buildings, malls, offices, etc. must make the maximum use of natural light. This paper reviews the active daylighting systems with the application of fiber optics to make them more efficient and cost-effective. A design of sun-pipes with quartz optical fiber and a control switch for attaining all the targets of high efficiency in the climate of India is proposed through this study.

For the labyrinth trap regulating valve, combined with the principle of multistage step-down principle, the boundary conditions are set according to the actual working conditions. The k − ε turbulent model is used to simulate the internal flow field of the labyrinth valve, and the influence of valve opening on the flow field is studied. According to the relevant design theory of labyrinth disk, the flow resistance coefficient and flow coefficient under different valve openings are calculated, and the flow characteristic curve is fitted and compared with the ideal curve. The results show that the flow resistance coefficient decreases linearly with the increase of opening. And the change of opening has little effect on the average velocity of the flow field. The research results provide an important reference for the design of labyrinth valve.

Recent literature review shows an increasing number of new product introduction (NPI) projects realized in manufacturing sectors. The study implemented NPI using Scrum, a highly regulated team-based framework to complete a project progressively. Scrum is a popular framework adapted from the agile methodology to develop complex products and systems. The case study involved contract manufacturing (CM), and the customer actively participates in NPI and contributes to decision-making. Scrum successfully broke down, prioritized, and performed project tasks in successive cycles. The case study demonstrated the potential of applying Scrum in NPI to ensure the adherence of customer requirements, especially the timely fulfilment of the milestones.

Machining of metallic biomaterials causes a slew of issues, including cutting tool wear and poor surface quality owing to inefficient tool design, which leads to excessive heat output. The objective of the research is to evaluate the wear of developed of uncoated carbide endmill tool with rake angle varied from positive to negative value in dry machining Stellite 21. The fabricated endmill is tested at Fanuc Robodill α-T14iFb with cutting conditions parameters are kept constant; including cutting speed (Vc): 60 m/min, feed rate (f): 153 mm/rev, and depth of cut (ap): 0.2 mm, throughout the cutting trials. The accuracy of fabricated endmill, wear mechanism, cutting force, and surface roughness were measured using Dino-Lite Microscope, Scanning Electron Microscope, Neo-Momac Dynamometer and Mitutoyo Surface Profiler, respectively. The result shows that by using a positive rake angle, the phenomenon of tool wear is reduced, and directly reducing the surface roughness and cutting force. Based on energy dispersive x-ray (EDX) element analysis, presence of oxygen in the cutting process which indicates the occurrence of oxidation wear on cutting tool. Extended observation of wear mechanism show high content of chromium on the flank face is revealed that indicated the diffusion wear on tools has occurred. In conclusion, the enhancement of tool geometry of endmill cutting tool is a key step toward sustainable manufacturing of high-end applications in biomedical industries.

Problems on laser weld quality still remain as vital issue even though the process was done with optimized condition which results the demand on robust monitoring method during the process. Until recently, many methods have been explored and air-borne acoustic are among of methods that have been proven to be able to detect the presence of defect. However, despite detection, it is essential if the type of defect could be identified as it gives different severity level to the development of failure. This work presents the identification of defect during pulse mode laser welding through the analysis of sound. In achieving the goal of this study, bead on plate weld have been done onto the 22MnB5 boron steel plate repeatedly based on 3 different set of experiment with the variation in the level of parameters. Simultaneously, time-series sound signal was acquired along the process before it was converted into frequency spectrum before further analysis. According to the result, it was recorded that the variation of parameters level in pulse mode laser welding process lead to the presence of porosity and crack. Relatively, the trend of sound frequency spectrum were also significantly changes its trend in respond to the parameters level variation. It was discovered that the dominant frequency for the signals acquired from the process which produce good quality weld, porosity and crack recorded the same range which was between 5 to 7 kHz. Uniquely, the existence of porosity could be identified by the occurrence of peak at around 9 kHz while the presence of crack could be recognized by the occurrence of peak at 8 kHz and 11 kHz. This trend was proven to be consistent in repeated experiment according to the result from principal component analysis. Based from the result in this study, it could be conclude that the identification of defect could be done by the analysis of the acquired sound during the process. Significantly, this would expand the ability of acoustic method for quality monitoring purpose as the identification of defect is also important in quality control.

The recent advances in manufacturing technology have led to the development of miniature products in the field of automobiles, aerospace, and robotics. Laser micro-drilling has developed as a potential substitute over conventional machining due to the advantages of operational precision, reduced operational costs, and a high-speed production rate. This process involves high power intensity from the laser to break down the bond between molecules of the workpiece and hence form a hole on the workpiece. This project aims to study the effect of laser power on the drilled hole geometry and to analyse the mechanism of the hole formation during laser micro-drilling. The material used in this project is SS304 sheet metal. The holes’ geometry and hole formation will be analysed by using an optical microscope. The size of the hole diameter for each power is almost the same in the range of 101.669–102.978 μm for the frontside. Meanwhile, the diameter of the backside hole increases from 64.343 μm to 88.852 μm at 15 W to 21 W of laser power respectively. For hole formation, the more material is ablated as the ablation process advances. As a result, the removal area from the micro-drilled hole grows from 3577.852 to 6516.237 m2. The shape of the hole is irregular due to the uneven power distribution of the laser towards the SS304 sheet metal when it undergoes an ablation process.

Reflow soldering is a process to create joining between the board and electronic component in order to make sure the electronic devices may function well. The aim of this study is to determine the solder joint strength through simulations using data from previous researchers. Two type of solder alloys were used namely Sn3Ag0.5Cu (SAC305) and Sn0.7Cu (SC07) with two types of substrate such as laminated copper and pure copper. Simulation was conducted using Fusion 360 software. Besides, the information and data on intermetallic compound formation and growth, as well as thickness were gathered and presented in this study to support the simulation results. Results showed that pure SAC305/copper substrate produced lower shear strength which was 15.17 MPa as compared to SAC305/laminated copper with the value of 26.67 MPa. Meanwhile SC07/pure copper also gave lower shear strength which was 5.62 MPa as compared to SC07/laminated copper which was 5.45 MPa. In terms of IMC, it was found that mainly Cu6Sn5 was formed at the solder joint interface with an average thickness of 3 µm for SAC305, and 5 µm for SC07 for both substrates. Hence it can be concluded that SAC305 with laminated copper substrate showed a good performance to produce a reliable electronics product.

The opening position is one of the factors that affect the ventilation performance of a building. In this study, the effect of opening position on natural cross ventilation of isolated building was investigated. The airflow pattern and ventilation rate under different opening configurations were analyzed. Eight different opening configurations were considered, including aligned and unaligned openings, as well as vertical-opening design. Computational fluid dynamics (CFD) simulation with 3D steady-state RANS equation Shear Stress Transport (SST) k-ω turbulence model was used. The parameters of streamwise dimensionless wind speed ratio ( $${\text{U}}/{\text{U}}_{{{\text{ref}}}}$$ U / U ref ), pressure coefficient ( $${\text{C}}_{{\text{p}}}$$ C p ) and dimensionless flow rate (DFR) were analyzed in this study. The results show that the aligned opening configuration Top-Top has the highest DFR at 0.60. This result is similar to that obtained from the literature. In addition, the design of vertical openings can improve the DFR of the building. The DFR of the building is mainly affected by the position of the opening on the windward side. This concludes that the opening positions exert an imperative role in affecting the internal airflow pattern, air recirculation and DFR of a naturally cross ventilated building.

Laser heating is a process that uses laser as a heat source. In this paper, the copper surface temperature during the laser heating process was studied by controlling the laser frequency and focal length. The laser heating experiment was conducted using a fiber laser marking machine and irradiated with a constant 27 W laser power within a duration of 51 s. The laser frequency and focal length were varied from 100 to 300 kHz and −3 cm to +3 cm, respectively. Meanwhile, laser surface modification (LSM) was performed on the copper rod surface to enhance the laser energy absorption. Furthermore, the defocusing modes for laser heating were used to analyze the variation of temperature. The focus point of the focal length for this experiment was set up at 18.4 cm from the focal plane and denoted as 0. Laser frequency and focal length were found to play an important role in increasing the surface temperature during laser heating since it affects the heat input delivered to the materials. It was found that the surface temperature reaches a higher degree, 879.2 °C with the combination of 200 kHz laser frequency at focal length 0.

This research was initiated to investigate the effect of surface roughness when machining slanted thin-walled pocketing profiles with various flank milling machining strategies. In this research, Multi-Axis Flank Contouring strategies namely Combin Parelm and Combin Tanto were the main machining strategies to machine an actual chosen aero-structural sample with slanted thin-walled of 105º and 85º. Samples of physical machining were obtained from a five-axis CNC milling machine DMU 60 Monoblock with Siemens 840D controller. The material used was aluminum AA6063 and the cutting tools were carbide K10 material of two flutes end mill with diameter 12 and 6 mm uncoated. At the end of this study, an analysis with regard to the surface finish was performed utilizing Mitutoyo surface roughness tester to measure the surface roughness of the machined part specimens. Three different sections namely approach, middle, and leaving area of the slanted thin-walled were taken for further analysis. In addition, the arithmetical roughness (Ra) value is used to measure the overall surface finish quality. The Combin Tanto strategy resulted better surface quality in comparison to the Combin Parelm strategy due the overwritten of depth of cut which occurred during the machining process although was set constantly. The tool trajectory and tilting position were believed to be the main factors affecting the surface finish of the machined part. The orientation of the cutting tool affected all the three areas evaluated and lead to an uneven depth of cut amount during the machining process.

Common microscopy approaches are considered as destructive technologies for porosity characterization in metallic parts for various engineering components. They are not only time consuming, but also causes wastage of materials due to the need of fabricating numerous batches of specimens just for such characterization. However, X-ray computed tomography has recently emerged as a viable technique to evaluate the porosity content in metallic components without the need of physically damaging them on purpose. Therefore, in this study, X-ray computed tomography and conventional 3D optical microscopy cross-section analysis approaches were used to compare the porosity profile obtained in 316L stainless steel additively manufactured using selective laser melting. both X-ray computed tomography and optical microscopy results both consistently show high densification (>99%) and low porosity (<0.7%) levels, suggesting optimum processing parameters were selected for the selective laser melting process. Similarly, the results of pore size, morphology, and distribution also compare well between both techniques. Overall, X-ray computed tomography is proven to be an effective non-destructive technique to assess porosity and defects in additively manufactured parts.

The awareness of lead-free solders can be attributed to their environmental and human-health related benefits. Due to this consciousness, research toward lead-free solder alloy became a concern. Tin-copper (SnCu) solder alloy is one of the candidates that can meet the characteristic of tin–lead (SnPb). The objective of this study is to analyse the wetting behaviour, intermetallic compound (IMC) thickness and also the spread ratio by varies the copper weight percentage (Cu wt%) in SnCu solder alloy. Solder alloy used was Sn-xCu, where x = 0.0, 0.3, 0.5, 0.7, 1.0 which was soldered onto electroless nickel immersion gold (ENIG) substrate using carbon dioxide (CO2) laser. Parameters used for laser soldering was 35 W for the laser power, focal length was kept constant, scanning time was 0.04 s, and scanning speed was 100 mm/s. Then these sample were subjected to isothermal aging with the duration of 0, 200, 500, 1000 and 2000 h. In the final analysis, the IMC thickness and wetting behaviour characteristics were characterized by metallographic microscopy. The results showed that the higher the Cu percentage in the solder alloy, the higher the thickness formed at the solder joint interface. Besides that, the morphology of IMCs additionally changed with aging time whereby it changed into much uniform and continuous shape, Nonetheless, its thickness was found to be increasing upon aging duration. Furthermore, the spread factor and spread ratio increase, but the equilibrium contact angle decreases with increasing Cu content. These results were the proof that Sn-0.7Cu/ENIG offers a good solder joint performance as compared to other copper percentage.

Peridynamics (PD) represents a new non-local theory of continuum mechanics which uses integro differential equations instead of the typical local partial differential equations in its formulation. Thus, it is suitable for modelling fracture mechanics, where a continuum domain is modelled through particles connected via physical interactions. The PD formulation allows us to model spontaneous crack initiation, and crack branching without the need for special mathematical treatment. The value of parameters such as particle discretisation and horizon size will be checked to make sure that it agreed to the result from Finite Element Method (FEM) in elastic deformation before proceed to the failure mode. In PD, failure criterion is established when its stretch value exceeds a prescribed critical stretch value. In the classical bond model or Prototype Microelastic Brittle (PMB), the bond force grows linearly with the bond stretch, and the value suddenly goes down to zero when the bond stretch exceeds its critical value. This study will focus on the effect of horizon size and particle discretisation on PD displacement of elastic analysis, and damage patterns with PMB damage model. The proposed study leads to a better understanding of how horizon size and particle disretisation affect the damage patterns in PD frameworks.

The application of laser bending of thin sheet metal are quite limited given that this forming process is widely used in various industries. The aim of this paper is to study the effect of laser power and laser scan passes on bending angle of stainless steel AISI 304 lasers bending. This study considers using parametric combinations of laser power and laser scan passes (number of loops) as the laser bending process parameters. The corresponding effects of these process parameters on bending angle of stainless-steel thin sheet metal (t = 0.1 mm) was observed. The results obtained shows that the bending angle increased with increased in laser power and laser scan passes, meaning that these parameters does significantly affect the bending angle. Other than bending angle, there were also a few bulges observed at certain location along the laser scan path for certain parametric combination of process parameters tested.

Since 40 years ago, several methods and techniques in semisolid metal processing (SSMP) for forming globular microstructures have been found. SSMP is a relatively new technology that occurs between the liquidus and solidus temperatures. One of the common techniques used to improve microstructure formation in the aluminium processing industry is grain refinement. The purpose of grain refinement is to refine the size of the grain structure and enhance the mechanical properties. Grain refinement is also utilised in SSMP to improve the formation of globular microstructures. This article intends to discuss various approaches employed in the laboratory or in the industry in recent years to produce globular microstructure feedstock for SSMP, particularly with grain refinement technique.

Traditional machining is limited to the assembly of parts. The emergence of 3D printing breaks this inherent thinking. The concept of "layer" is different from flat printers, and innovative and unique additive manufacturing processes are used in various fields. However, FDM printing and molding problems are closely related to thermal characteristics. This article reviews the causes and solutions of FDM 3D printer molding problems. Introduce the research on structure design and process parameters of printer. Furthermore, a theoretical study on the influence of thermodynamic properties in the FDM process is put forward. That is to study the internal relationship between plastic fuse and thermodynamics, which provides a scientific basis for solving common problems of FDM type 3D printing. In the future, the challenge facing FDM printing is how to find out the relationship between the thermodynamic properties of plastics and the influence of printing. This puts forward the idea based on structural adaptation and neural network learning, which can be used in actual printing production situations.

By analyzing the filtering mechanism of the filter bag and the deficiency of static injection method based on fixed pressure difference, three models are selected to predict the pressure difference data. Experimental results show that all three models can predict the change trend of the pressure difference data. The MSE of BP neural network is 0.00994, indicating that the pressure difference data is predictable. The method of dynamic injection with pressure difference as control parameter is feasible. In order to solve the problem of flood of fault alarm information of pulse bag filter, the unsupervised learning method in machine learning was analyzed for the data set of fault type. By comparing the unity of the classification results of the three algorithms, it was found that 67% of the three algorithms have the unity 1, and the unity rate of the three algorithms was greater than 0.998 under different K values. It is proved that this classification algorithm is feasible and has good prediction accuracy.

The main purpose of this research is to study on a particular procedure for the tooling design due to the design requirements, parameters of the mold and relationship with the plastic injection molding process that can be time-consuming and quite costly. The detail about the design procedure by using CAD/CAM software such as SolidWorks and CATIA are explained. In order to design the mold that has the completed components i.e. leader pin, ejector pins, spruebushing, cooling channel and gate, the mold design need to be prepared of the part design that must be the first design in SolidWorks and then it is exported into CATIA for the mold tooling design process. Finally, the analysis process is conducted by using e-SimpoeWorks to determine the filling time, mold temperature and molten material temperature. It is found that the mold is designed for the vehicle part based on five steps in the procedure and must be suitable to be setup on the injection molding machine. In addition, the output is recommended to be used further for machining of the mold and 3D/4D/5D printing of the additional vehicle part features in the subsequence manufacturing process.

Nowadays, stainless steel is widely used in laser processing applications, including laser heating, laser brazing, and laser welding. However, it has poor optical properties due to low laser energy absorption. However, this could be improved with the aid of laser surface modification (LSM). The significance of this work is to examine the influence of LSM laser power on the surface roughness of 316L stainless steel samples. First, the LSM laser power was varied from 15 to 27 W. Then, the surface topography and variation of the surface roughness values were examined by using a 3D optical microscope. Furthermore, the modified surface by LSM will be heated using laser radiation in order to analyze the effect of surface roughness towards laser heating temperature. The result revealed that as the LSM power increased, thereby resulting in an increase of surface roughness. The highest LSM laser power (27 W) produced the highest surface roughness with 28.98 μm. Experimental results illustrate that the heating temperature were increased 36%, corresponding to a polished flat reference surface, which indicates the increment in energy absorptivity.

A vortex tube is an intriguing, simple system capable of producing cold and hot streams at room temperature from a single compressed fluid supply. It is commonly used as a cooling system in many industrial applications because of its remarkable cooling capability and simplicity with no moving parts. This vortex tube does not need any refrigerants or chemical fluids to function as intended as a cooling device. The usage of the vortex tube as a cooling device that has been implemented in a cooling necklace has less to no substantial research data. Therefore, it is hard to determine the best possible outcome that could be achieved by integrating the vortex tube with a cooling necklace. Thus, the main objectives for this research are to determine the performance of vortex tube as a cooling device on a cooling jacket at different cold mass fraction and also to determine the performance of vortex tube as a cooling device on a cooling jacket at different inlet pressure. In this particular research, an experimental study was conducted in two different situational environments, one in a controlled environment which is indoors while the other is outdoors with direct sunlight to simulate real-life situations where the cooling necklace might be used. It can be concluded that cold mass fraction of 0.4 and the highest inlet pressure of 0.4 MPa are the optimum values to obtain the lowest temperature inside of the cooling jacket.