Proceedings of the 2nd Energy Security and Chemical Engineering Congress

Offshore oil and gas platforms are one of the energy industries that generate huge amount of waste heat and CO2 emission that cause environmental impacts. This paper performed an investigation on the potential source of waste heat on the offshore oil and gas operation. Brief explanation on the standard operating strategy of the offshore platform was given and the processes that released huge amount of recoverable waste were emphasized. The waste heat recovery (WHR) is a method of capturing and transferring the waste heat from a process with gas or liquid to the system as an additional energy source. Technologies that were utilized by previous researchers were reviewed and the future direction on the waste heat recovery of offshore operation was described. The oil extraction and processing platform which is also known as the “Central Power Platform” was discovered to be the main source of waste heat and the processes involved were the potential candidates for waste heat recovery. Although there have been studies utilizing different technologies on the waste heat recovery of offshore oil and gas sector, more improvement could be made in the future to the efficiency of the power system by applying other WHR technologies such as turbo compound or combination of several WHR technologies to recover more waste heat, hence reducing environmental impacts.

Researchers have analyzed Organic Rankine Cycle (ORC) recently on its potential for waste heat recovery (WHR) on offshore oil and gas platform. However, there is still no practical application of ORC on this sector currently. An extensive overview of the ORC for offshore oil and gas platform has been performed in this paper. The discussion investigates the capability of this technology as the WHR for offshore oil and gas platform application. In this study, a brief explanation of the process that happened on the offshore platform which is the potential source of waste heat to be recovered will be given. The studies conducted by previous researcher on the offshore application were reviewed and the benefits of ORC were emphasized and some information on the configuration of the ORC on offshore oil and gas platform were described. ORC was found to be able to adapt to low or medium grade which is between 150–400 °C heat source with different type of configurations. The flexibility of ORC makes it easier to be used on offshore oil and gas platform with different configuration and contribute to many advantages. The electricity generated can increased up to 20.3%, 11.3% increase in the overall system efficiency and 18.3% in the utilization factor. Furthermore, an average reduction of 22% in the fuel consumption and CO2 emissions could be achieved over the platform operating years. Dry and isentropic fluids are more suitable to be the working fluid of ORC system on offshore application which could lead to better system performance and efficiency. Cyclopentane had been widely used as it is thermally stable in the temperature range between 220 and 350 °C. From the economic aspects, although involving ORC could increase the initial investment cost up to 46%, it also increases the net present value, leading to a discount rate up to 10%.

The propeller-type swirler has been mentioned several times in the literature as one of the decaying flow swirlers designed to improve heat transfer performance while maintaining a low friction factor. However, the distance travelled by swirling flow varies according to the swirler’s design configuration. As a result, the purpose of this paper is to investigate the heat transfer performance and friction factor of a new turbine-like decaying flow swirler (TDS). The distance traversed and decays downstream the tube by the created swirling flow will then be determined. The TDS is a rigid turbine or compressor consist of four twisted blades at 172.2° set at the entrance of a fully developed 1.5 m tube with a dimensionless length (L/D) of 93.75. A 60:40% water and ethylene glycol mixture was employed as a working fluid for the turbulent flow with Reynolds numbers ranging from 4583 to 35,000. The results indicate that the maximum relative heat transfer is 1.16 and the highest relative friction factor is 1.47 at the lowest Reynolds number tested. For Reynolds numbers less than and equal to 10,136, the thermal hydraulic performance achieved unity. The obtained relative heat transfer is deemed to be poor in comparison to several publications. The swirl flow finally entirely decays after L/D = 70.32 after being visualised through the vortex core and cross-sectional plane of the tube, contributing to a reduced heat transfer performance. In conclusion, TDS performance can be optimised for a lower dimensionless length using the same design configuration, or the design configuration should be modified to increase the generated swirl flow intensity.

In this research, the optimal feed flowrate trajectories, and reaction temperature for autocatalytic esterification of sec-butyl propionate in the semi-batch reactor had been determined using dynamic-nonlinear programming (NLP) based optimization. The dynamic multi-objective optimization (DMOO) problem yielded from this autocatalytic esterification due to contrary objective functions. The DMOO problem was characterized by multiple solutions, which are non-dominated or Pareto solutions. In this work, to generate the Pareto solutions for the chosen objective functions, which maximize conversion and minimize process time, the ε-constraint approach and control vector parameterization (CVP) has been applied. Here, various combinations of conversion and process time were obtained as a result of different optimal temperatures and feed flowrates in each point of Pareto solutions. Finally, these solution methods could benefit industries in evaluating and selecting the trade-offs and operating policies.

A reduction of anthropogenic CO2 emissions and extensive demand for electricity has motivated cleaner power production. Renewable energy source from biomass features an alternative option for sustainable energy generation. Innovation in biomass gasification with combined heat and power (BG-CHP) system emerges as a potential technology to achieve and stimulate the Sustainable Development Goal 11 (SDG 11: Climate Change). Nevertheless, a major problem of BG-CHP is its bulkiness and inconvenient form of biomass along with the multifaceted process behavior. All these feature non-linearities as well as high process interactions, and therefore require a control advancement to ensure feasible and flexible operation. Two different types of controllers [viz; proportional, integral, and derivative controller (PID) and Model Predictive Controller (MPC)] are designed and evaluated to identify the best control system via set point tracking scenario. Embedment of MPC into palm kernel shell BG-CHP plant outperformed the performance of PID controller with minimal overshoot and precise set-point tracking. The findings obtained from this study are valuable in identifying the practicability of BG-CHP system as a sustainable and clean waste to energy (WtE) technology.

This paper presents the mechanical behaviour of pineapple leaf fibre (PALF) in oil palm shell (OPS) lightweight concrete (LWC). Various fibre volume fractions were considered which include 0.5%, 1.0%, 1.5% and 2.0% of PALF. In this study, the PALF was extracted and treated with sodium hydroxide solution with a 10% concentration. The length of the PALF was made constant as 40 mm based on the optimum fibre length obtained from previous work. The experimental testing in this work includes slump test, compressive strength test, splitting tensile test and four-point bending test. Results showed that the compressive strength decreased at all ages with an increase in PALF volume fraction, whereas improvement in strength was observed in both splitting tensile strength and flexural strength. The inclusion of PALF increases the tensile and flexural strength up to 3.28 MPa and 6.55 MPa respectively. The findings revealed that 1.0% PALF is the optimum fibre volume ratio for tensile and flexural strength. The oven-dry density and demoulded density of all OPS concrete mixes fall within the range of 1526–1731 kg/m3 and 1787–1853 kg/m which are in the range of structural lightweight concrete. The splitting tensile strength of OPS and PALF reinforced OPS-LWC in this study falls in the range to that of conventional concretes. Flexural strength to compressive strength ratio showed that all PALF reinforced OPS concretes had ratios ranging 12–22% which were greater than the usual range for lightweight aggregate concrete. Hence, this indicates that PALF fibre can improve significantly the flexural strength of OPS lightweight concrete.

The article discussed about pedal misapplication or pedal error among Malaysian drivers. The variability of driver’s foot movement could result in an error in foot placement. The farther the foot from the intended pedal, the larger the potential errors to occur while hitting the pedal. The goals of this research are to conduct a study to determine the Malaysian driver’s foot placement on pedal and the total emergency braking response during the normal driving and emergency braking situation, and also to define the sources of foot placement errors and factors which contributing to the wrong pedal placement among Malaysian drivers. The scopes of this research are to develop a test setup to determine the foot placement on pedal by using video observation and measure the total emergency braking response by using force sensor, to determine the source of foot placement errors and to define the factors contributing to the wrong pedal placement. The study is limited to automatic transmission car, Malaysian drivers aged from 20 to 65 years old. In order to conduct the naturalistic driving test, an instrumented car is prepared and equipped with some important instruments such as cameras, force pressure sensor, light cue device, audio cue device and Arduino hardware. A study has been successfully conducted to determine the Malaysian driver’s foot placement on the pedal during the emergency braking. According to our research, 10% of the participants from the driving study conducted use both legs while driving and press the brake pedal using their left foot during emergency braking. It is dangerous for other drivers because the brake light can turn on at any time, causing other drivers to become distracted.

Electrode manufacturing significantly affects the machining cost and time of the Electrical Discharge Machine (EDM). Therefore, many researchers investigated the metallization of 3D-printed electrodes for EDM as an alternative method to improve electrode manufacturing throughout the years. This study aims to investigate the metallization by Aluminum-carbon (Al-C) paste. Furthermore, the copper deposition of the metalized electrode was examined for different acidic bath concentrations and sample immersion duration. This particular electrode can be used in Electrical Discharge Machine (EDM). The electrode was fabricated by a Fused Deposition Machine (FDM). The material used to fabricate the electrode was Polyethylene Terephthalate Glycol (PETG). Aluminum-carbon (Al-C) paste is used for surface preparation as the first metallization step. This metallization method is environmentally friendly as electroless metallization eliminates the etching process. The samples have dipped 5 wt% of copper sulfate CuSO4 and 15 wt% of sulfuric acid H2SO4 for 24, 72 and 120 h for the copper deposition process. After the metallization, the characteristics of each sample were evaluated by scanning electron microscope (SEM), electrical performance measurement and microscopic testing. The average resistance for 24, 72 and 120 h were 1.0 Ω, 0.7 Ω, and 0.23 Ω respectively. The standard deviation was calculated for 24, 72 and 120 h, which were 0.5, 0.35 and 0.12 respectively. For the SEM observation, the presence of Cu on 24 h was not distinctly visible and the deposited Cu on the samples was 28.58%. For 72 h, the Energy Dispersive X-ray for the sample corresponds with 42.20% of Cu. Meanwhile, the growth of Cu deposition was visible for 120 h, where the Cu deposition was 80.85%. The microscopic testing for the thickness of Cu coated on the samples was measured. The average thickness for 24, 72 and 120 h were $$8.6_{ - 1.96}^{ + 1.51} \;\upmu {\text{m}}$$ 8 . 6 - 1.96 + 1.51 μ m , $$108_{ - 13.82}^{ + 13.19} \;\upmu {\text{m}}$$ 108 - 13.82 + 13.19 μ m and $$150_{ - 33.43}^{ + 10.82} \;\upmu {\text{m}}$$ 150 - 33.43 + 10.82 μ m respectively. Based on the results provided from all the tests, the 120 h sample has better Cu deposition than 24 h and 72 h. From the results, the longer the samples dipped in the acidic bath, the more the Cu deposition occurred.

Finding an effective, green adsorbent for removal of heavy metals is one of the main problems in water purification field. Cellulose has gain tremendous attention for its variability of purposes including heavy metal removal via adsorption. As a preliminary material study, Fourier Transform Infrared Spectroscopy (FTIR) would be a good step in analyzing the removal potential of an adsorbent. In this study, cellulose-based adsorbent extracted from Pandan leaves was subjected to acid hydrolysis after being pre-treated with alkali and bleaching treatment. The output material was then analyzed in this research using FTIR. The result showed that some components were removed after the treatments and the material has potential for future development as adsorbent for heavy metal removal due to presence of carboxyl group in the backbone.

Engine oils have traditionally served as the principal lubrication for combustion engines. With so many engine oils on the market, each has its unique set of ingredients and qualities that set it apart from the others. Customers are often influenced by the variety to switch between different types of engine oil. The wear resistance and lubrication properties of a few mixtures of different engine oil brands are investigated in this study. Three brands of engine oil were chosen and mixed in a 1:1 weight ratio. The viscosity, coefficient of friction (COF), and wear scar diameter (WSD) of the mixtures were determined using the Four-ball tribotester and viscosity testing equipment at three testing periods. The results demonstrate that the mixtures act differently than pure oil. Even though the mixing yielded more viscous lubricants, which is preferred, the data reveal that the COF and WSD also increased. The mixing might cause chemical interactions between additives, causing the oil's structure to change. According to this study, using pure oil is superior for extending the life of a combustion engine.

The characteristics of Indonesia's tropical climate by getting good sunlight throughout the year can be used as alternative and renewable energy. Stirling engine in general is a type of combustion motor that applies the principle of external combustion because the working system is done on the outside of the engine. The origins of the Stirling engine were discovered by a British scientist named Dr. Robert Stirling. This research using Parabolic Dish type powered by solar energy as a heat source. The Stirling engine is heated using solar energy from the Parabolic Dish. Hot cylinder as a displacer cover is varied by using different materials, namely stainless steel, copper, and glass. The results showed that hot cylinder material using glass gets the highest RPM of 131 RPM and indicated engine power of 0.0712 Watts.

The research of ergonomics in the glove manufacturing company was done in the production line. The workers performed most of the processes manually. Consequently, they were exposed to Musculoskeletal Disorders (MSDs) risk factors such as repetitive motion and awkward postures while working. In this case study, the Rapid Upper Limb Assessment (RULA) was used to determine the worker’s risk level of MSDs. It was based on a working assessment of video records and photos by the workers. The final RULA score found that the former changing process indicates the high risk of MSDs, investigating, and implementing change required. Besides, the final RULA score of glove rework scores a five. The score indicates a medium risk of MSDs, need further investigation, and change soon. Meanwhile, the glove packing process scored four which indicates a low risk of MSDs and changes might be needed. Other than, the Body Discomfort Survey was answered by the workers (n = 18), and the mean MSDs impact scores from the survey concluded that workers felt discomfort the most in the former changing (53,264.75), followed by glove rework (12,419.67), and glove packing (6313.33) process. The DELMIA software was then used to evaluate the improved body postures. The analysis provided the limitations of angular movement of body parts, allowing the manikin to bend at a minimum angle to fit the task while also reducing the final RULA score to an acceptable score.

The research of Quick Response Manufacturing (QRM) in the production supply chain activities of an organization are based on product planning control. A supply chain with a poor flow for instance in the company's logistics could cause the performance of the company. Inadequate preparation will result in mediocre quality, a loss of productivity and inefficiency. The objective of this thesis is to enhance the critical supply chain of a selected production line in the company by analyzing the existing data. From there, a simulation using software which is WITNESS, is conducted. The output from the simulation will be used in determining methods or solutions to enhance the supply chain related issues. The methods or solutions will be resulting in better efficiency, quality, and productivity. The data collected from the improvement will then be compared to the existing data to gauge whether the improvement contributes to the increase in efficiency and productivity of the selected line. The results from the simulation appear positive feedback, with an average of 85% of the busy time on the proposed layout simulation compared to 66% on the current layout. Even though the differences are minor, they can be critical during peak hours. Finally, the result obtained between the current layout and improved layout proves that the implementation of Quick Response Manufacturing (QRM) can increase the productivity of Dunham Bush company at Kajang, Selangor.

This study aims to determine the viscosity characteristics of TiO2-Polyolester (POE) nanolubricant and optimize it for heat transfer applications in compressor air conditioning systems. A magnetic stirrer was used to mix TiO2 and POE lubricant for 30 min. The nanolubricant was then ultrasonicated with a probe for 120 min to stabilize the TiO2-POE nanolubricant. There were seven different types of samples examined in this study, with concentrations of 0, 0.05, 0.15, 0.25, 0.35, 0.45, and 0.85 vol%. Rotational Rheolab QC was used to quantify viscosity from 30 to 90 °C. The viscosity of nanolubricant augmented as the proportion of nanolubricant increased. In contrast, when the test temperature rises, the viscosity drops. The greatest viscosity rise was 56.657% at 0.85 vol% at 80 °C, while the lowest viscosity increase was 0.029% at 0.05% at 30 °C. Based on the Response Surface Approach, optimization using the Multivariable Functions Optimization (MBFO) method with the Central Composite Design (CCD) type. The uncertainty analysis was also performed in this study. The most optimum dynamic viscosity is 34.8098 mPa s. At a temperature of 60 °C, this condition was achieved in samples with a concentration of 0.45 vol%.

The paper aims to expound on the comprehensive experimental investigation of the stability of TiO2-Polyolester (POE) nanolubricant. A magnetic stirrer was used to disperse TiO2 nanopowder into POE lubricant for 30 min. The six samples were then subjected to various ultrasonication treatments lasting 40-, 60-, 80-, 100-, and 120-min. Stability analysis was performed in three stages: visual observation, Ultra Violet (UV) visible spectrophotometric analysis, and measurement of the absolute zeta potential. The results showed that sample without ultrasonication treatment had substantial agglomeration as compared to other samples. The absorbance ratio of the sample without ultrasonication treatment is 0.33. The absorbance ratio value escalated as the duration of the ultrasonication treatment on the sample increases. After ultrasonication treatment for 40–120 min, the absorbance ratio increased by 34–117%. The samples treated with 120 min of ultrasonication showed the highest level of stability, as evidenced by the high absorbance ratio and zeta potential values of 0.95 and −80.48 mV, respectively. As a result, the findings suggests that TiO2-POE with ultrasonication treatment for 120 min could generate the excellent stability compared to other samples in this experiment.

The UV visible spectrophotometry technique is one of the methods for determining a nanolubricant’s stability standard. The absorbance level of a nanolubricant is determined by spectrophotometry. This method measures how well the nanolubricant absorbs UV rays from a light source. In this study, one factor at a time (OFAT) based on surface response was adopted to determine the effect of wavelength selection on the absorbance ratio of FAl2O3-POE nanolubricant. The FAl2O3-POE sample was prepared using a two-steps approach. The sample was ultrasonicated for 100 min using a homogenizer. UV visible spectrophotometry analysis was performed on day 1 and 15 to determine the absorbance ratio. Sixteen runs were performed using a quadratic design to acquire experimental data were fitted. The ANOVA analysis discovered that the experimental statistics were well suited to the polynomial model, with an R2 value of 0.9951 and a model F-value of 1316.47. The findings suggest that the optimum wavelength is 375 nm with an absorbance value of 0.935473 and a desirability level of 1.0.

The presence of a hydroxyl group on the surface of Al2O3 is responsible for the low level of stability of Al2O3-based nanolubricant. This paper aims to illustrate how the SiO2 functionalization approach can be used to modify the surface of Al2O3 nanoparticles. The effects of four different functionalization treatments on Al2O3 on the dispersion stability of FAl2O3-Polyolester (POE) nanolubricant were found to be significant. There are four samples with SiO2:Al2O3 ratios of 15:85, 30:60, 45:55, and 50:50%, respectively. Each sample was mechanically stirred for 120 min for adsorption process. Then, each sample received a sub-inter critical annealing treatment at 120 °C in the furnace for 180 min, after which the samples were chilled using the gradual cooling approach to avoid thermal shock on the FAl2O3 nanoparticle surface. Newly synthesized FAl2O3 was dispersed in POE lubricant for 30 min with a magnetic stirrer and then ultrasonicated for 100 min to prevent agglomeration. On day 1 and day 15, dispersing stability was examined using the UV visible spectrophotometry method to verify the wettability of FAl2O3 nanoparticles enhancement. The results reveal that increasing the SiO2 ratio in the functionalization process enhances the dispersion stability of FAl2O3-POE nanolubricant. The findings suggest that FAl2O3-POE sample with a 50:50 ratio has the best dispersion stability, as shown by the highest absorbance ratio value of 0.945.

Errors in the UV visible spectrophotometry analysis’ selection of spectral peaks can lead to errors in the nanolubricant stability analysis. Despite the fact that the spectral peak results are compared at the same peak, it is critical to identify the correct spectral to avoid errors in the nanolubricant stability analysis results. In this study, one factor at a time (OFAT) based on surface response was adopted to determine the effect of wavelength selection on the absorbance ratio of TiO2-POE nanolubricant. The TiO2-POE sample was prepared using a two-steps approach. The sample was ultrasonicated for 100 min using a homogenizer. UV visible spectrophotometry analysis was performed on day 1 and 15 to determine the absorbance ratio. Sixteen runs were performed using a quadratic design to acquire experimental data were fitted. The ANOVA analysis discovered that the experimental statistics were well suited to the polynomial model, with an R2 value of 0.9970 and a model F-value of 2154.24. The findings suggest that the optimum wavelength is 500 nm with an absorbance value of 0.901239 and a desirability level of 1.0.

This project aims to investigate the effects of capillary size and shape toward the brain tissue poroelastic properties model using asymptotic expansion homogenization (AEH). Applying AEH to the existing poroelastic governing equations (GE) results in a new GE consists of 6 macroscale equations and 4 microscale cell problems. The cell problems are solved on a microstructure geometry of brain tissue with capillary embedded to obtain effective parametric tensors, namely the capillary and interstitial hydraulic conductivity ( $${\mathbf{K}}$$ K and $${\mathbf{G}}$$ G ), capillary and interstitial homogenous Biot’s coefficient ( $$\alpha_{c}$$ α c and $$\alpha_{t}$$ α t ), Young’s modulus (E) and Poisson’s ratio (v). By varying the tortuosity, the percentage difference of $${\mathbf{K}}$$ K is 97.98%, shows that it is highly affected by tortuosity. The percentage difference of $${\mathbf{G}}$$ G is 0.25% implying that tortuosity insignificantly affecting $${\mathbf{G}}$$ G . Meanwhile, $$\alpha_{c}$$ α c and $$\alpha_{t}$$ α t decreases and increases with tortuosity, respectively. The percentage difference of E and v are 0.14% and 0.03% respectively, implying that both parameters does not affected by tortuosity. Besides, $${\mathbf{K}}$$ K is exponentially increases with the increase of radius. On the other hand, $${\mathbf{G}}$$ G decreases as the radius increases. Meanwhile $$\alpha_{c}$$ α c and $$\alpha_{t}$$ α t increases and decreases, respectively as radius increases. The percentage differences of E and v are 18.26% and 14.55% respectively, suggesting that they are significantly affected by the radius. In conclusion, capillary shape and size have significant impact on the simulation of human brain. Thus, both characteristics should be precisely emphasized in the development of the geometry so that accurate parameters can be obtained to solve macroscale equations in future.

Friction is one of major concern in mechanical movement while the lubricant is one of solution to counter it. The additive of nanoparticles in lubricant may improve its tribological performance. The current study focusses on the effect of SiO2 and TiO2 nanoparticles as additive in PVE lubricant. The new solution namely nanolubricant was prepared at three different concentrations. The nanolubricants were characterized using TEM and its stability was evaluated up to 30 days. Four-ball method was used to determine the effect of nanoparticle concentration on coefficient of friction (COF) and wear scar diameter (WSD). The results reveal that nanoparticle additive provide better COF at low volume concentration. The COF for nanolubricant at volume concentration less than 0.010% for TiO2 and less than 0.005% for SiO2 attained lower than pure PVE lubricant. The results for WSD also were in agreement with the trend of COF. Therefore, the nanolubricant has potential to provide better friction coefficient performance for lubrication application.

Waste in oil palm biomass is one of the renewable energy sources that can be converted into energy. The availability of oil palm biomass which is a renewable energy source is currently very adequate. This research will specifically analyze the differences in the level of thermal efficiency and heat transfer rates of two different types of biomasses. In addition, this comparative analysis was also carried out when testing the modification of the perforated plate with the standard plate or without modification. The combustion test was carried out in a fluidized-bed combustor (FBC) combustion chamber with data measurements using a Digital Thermometer brand Hot-Temp HT-306. Palm oil solid waste biomass such as palm kernel shells and oil palm fronds were used as testing fuel in this study. The results show that the average level of thermal efficiency for palm kernel shell (PKS) and oil palm midrib (OPM) fuels, when tested with a modified hollow plate, is 33.59% and 28.31%, respectively. Meanwhile, the results of the average thermal efficiency at the time of testing the standard plate were 19.77% PKS and 28.29% OPM. The results of the heat transfer rate test for standard plates with PKS fuel are 7363.53 W/m2, which is lower than after modification, which is 7762.38 W/m2. Meanwhile, the results of combustion using OPM fuel were higher when testing the standard plate at 7289.84 W/m2 compared to 7162.81 W/m2 when testing with a modified perforated plate. Overall, testing with the application of modified perforated plates can increase the thermal efficiency and heat transfer rate in the FBC chamber.

Biodiesel is an alternative source of non-fossil fuels for diesel engines and can be used without the need for engine modifications. The effects of employing low proportions of palm biodiesel blends on marine diesel engine performance are investigated in this study. Response surface methodology (RSM) model had been employed to determine the optimal operating conditions of marine diesel engine with respect to palm biodiesel blend, engine load and speed. The ANOVA analysis was selected to verify the adequacy of the model. The use of palm biodiesel blends has lowered the CO emissions while increasing BSFC and NOX emissions marginally. The results of statistically goodness of fit (R2) and the goodness of prediction (Adjusted R2) for all response parameters were above 90%. This value indicates that the developed model is able to predict the data with high accuracy. This study revealed that the optimum condition of fuel was determined as 5% palm biodiesel and 95% of petroleum diesel which operated at 1500 rpm speed and 36.97% engine loading with 78% of RSM desirability. The RSM model was tremendously helpful in structuring the experiment and lowering the amount of time required by reducing the number of experiments to be conducted.

The present study aims to investigate the effect of changing air conditioning refrigerants and compressor lubricants on system performance. Two types of refrigerants namely R410a and R32 paired with two different lubricants were investigated. A test rig consists of residential air conditioning with a thermal control room was developed in the present study. The initial refrigerant charge was varied to determine the optimum charge for each refrigerant-lubricant mixture. The results reveal that the optimum charge for R32 is 350 g that represents only 70% of the refrigerant amount for R410a. R32 performs better than R410a for both lubricants mixture. The R32-POE combination shows the best performance with 14% improvement from the baseline data. R32 performs better in the air conditioning originally design for R410 refrigerant and has a good prospect to replace R410a as a more environmentally friendly refrigerant.

Essentially, composite materials are formed by combining two or more constituents with different properties to obtain a new material with unique combination of features, thus has potential to provide value-added properties absent in one of the constituents. In this paper, the effects of glass particle size on mechanical properties of epoxy composite materials, such as stress, strain, and Young's modulus and its relationship with the particle volume fraction are investigated by using Finite Element Analysis of Ansys Mechanical APDL. A 2D micromechanics model based on variation asymptotic method for unit cell (VAMUCH) was employed for this study. The research study comprises of two cases: (1) the comparison of different size of glass particle filler from nano to micro size, and (2) the comparison of volume fraction of glass particle ranging from 5 to 25 vol% towards the mechanical properties of epoxy resin. The results of the first case study demonstrated that the stress and strain against gradient displacement is slightly increased for all modelling samples. In fact, the smallest area size particle of 7.85 nm2 produces the highest value of Young’s modulus 3.66 GPa. Similarly, for second case study, it is found that the highest Young’s modulus 5.14 GPa was achieved at 10 vol% glass particles, which is about 91% increment compared to unfilled epoxy. Therefore, concludes that as the size of glass particle getting smaller from macro to nano size, and the volume fraction of glass to epoxy is lower, then the Young’s modulus of composite increases.

The idea of a tuned mass damper emerges due to a common vibration problem existed in mechanical and civil structures applications. Vibration turns out to be a hazard that can reduce the life of the structure, thus tuned mass damper is considered as one of the most practical methods in the engineering branches since it can be used as vibration attenuator. The present paper investigated the design of tuned mass damper (TMD) to reduce the vibration amplitude of a building structure model. In the initial stage, the frequency of the building model and tuned mass damper were determined by using the theoretical equations. This is followed by the finite element modal analysis to determine the natural frequency and mode shape and then compared with the calculation. It was found that the percentage error of natural frequency between the theoretical and the simulation result was less than 15% for building model (without tuned mass damper) and 2% for building model with attached tuned mass damper. The simulation analysis was further carried out by utilizing tuned mass damper to suppress vibration on the building model when subjected to a 10 N force. The results demonstrated that the attachment of TMD on the building model could significantly reduce the vibration amplitude by more than half.

Investigations of the frequency and vibration levels of the internal combustion engine have been intensively carried out to minimize and make the driver comfortable. This experiment was mostly done by changing engine materials and also testing various suitable fuels. In the last few decades, the analysis of the frequency of internal combustion engines has been carried out by making mixtures of alcohol fuels and fuel additives. The purpose of this work is specifically to analyze the frequency level comparison in an internal combustion engine using a petroleum-methanol fuel mixture (G95%-M5% and G100). The experiment in this test was tested five times with engine speed (1000 rpm, 15,000, 2000, 2500, and 3000 rpm). The test results show that the mixed fuel can produce a lower combustion frequency. However, the burning speed is slightly slower than that of pure petroleum fuels. While pure petroleum fuel has a burning speed so that the level of vibration frequency produced is slightly high. Overall shows that the fuel mixture applied in this work can reduce the level of vibration frequency in the internal combustion engine.

Nanostructured coating that possessed high density of grain boundaries enable excellent physical coverage of the coated surface against corrosion and mechanical problems compared to the larger grain size of particles found in conventional paint. The current study focusses on the effect of SiO2 and TiO2 nanoparticles as additive in acrylic automotive paint for corrosion. The new paint namely nanopaints was prepared at three different concentrations. The nanopaint were characterized using Electro-chemical test and the open circuit potential (OCP) is recorded. Electrochemical test in a saltwater solution method also used to determine the potential of nanopaint concentration on automotive surfaces. The results reveal that nanoparticle additive provide better corrosion rate as compared to the original basecoat. The optimum anticorrosion behaviour for both TiO2 and SiO2 nanopaints were achieved at weight percentage of 1.5 wt% and 1.0 wt%, respectively. Therefore, the nanopaint has potential to provide better corrosion performance for automotive surface application.

Bulk metallic glass (BMG) based on lanthanum is one of the BMG with exceptional glass-forming ability (GFA). The $${\mathrm{La}}_{61.4}{\mathrm{Al}}_{15.9}{\mathrm{Ni}}_{11.35}{\mathrm{Cu}}_{11.35}$$ La 61.4 Al 15.9 Ni 11.35 Cu 11.35 bulk metallic glasses were treated to a laser processing test in this experiment. The results showed that the best power, frequency, and speed ranges for laser processing of the $${\mathrm{La}}_{61.4}{\mathrm{Al}}_{15.9}{\mathrm{Ni}}_{11.35}{\mathrm{Cu}}_{11.35}$$ La 61.4 Al 15.9 Ni 11.35 Cu 11.35 BMG samples are 40–50 W, 160–240 kHz, and 200–400 mm/s, respectively. As a result, the current work was effective in producing the Lanthanum-based functionally graded material (FGM) BMG. The positive findings on the laser’s microstructural or morphology, give a solid foundation for future advancement research on the $${\mathrm{La}}_{61.4}{\mathrm{Al}}_{15.9}{\mathrm{Ni}}_{11.35}{\mathrm{Cu}}_{11.35}$$ La 61.4 Al 15.9 Ni 11.35 Cu 11.35 BMG.

Response surface methodology (RSM) was used in conjunction with the miscellaneous design model to identify prediction models for the thermophysical properties of a hybrid cellulose nanocrystal-copper (II) oxide nanolubricant. Minitab 18 statistical analysis software and Response Surface Methodology (RSM) based on Central Composite Design (CCD) were utilised to generate an empirical mathematical model investigating the effect of concentration and temperature. Analysis of variance (ANOVA) is used to validate the significance of the developed empirical mathematical model. Thirteen experiments were conducted to obtain second-order polynomial equations for the desired specific heat capacity, thermal conductivity, and dynamic viscosity, outputs. The predicted values were found to be in reasonable agreement following the investigational finding. In addition, the models could predict more than 80% of the nanolubricant output variations, indicating that the model is accurate. In the optimization plot, the predicted optimal values for dynamic viscosity, thermal conductivity, and specific heat capacity are 2.3631, 0.1463, and 1.6311, respectively. The relevant parameters are 90 °C and 0.1 for temperature and concentration, respectively. The plotted composite is 0.6531. The findings of the percentage of absolute error (POAE) reveal that the model may precisely predict the optimum experimental parameters.

This study aims to investigate the effect of laser parameters on the development of superhydrophobic surfaces by using nanosecond laser texturing with a chemical coating. Ti6Al4V specimens were ultrasonically cleaned before applying silicone oil and laser textured onto the material surface. Nanosecond laser texturing is executed in an argon environment by varying several parameters, such as laser power, laser scan speed, and hatching distance. After that, the textured specimen was again ultrasonically in an acetone bath to clean the surface. Superhydrophobic surfaces are determined by measuring the water contact angle using the sessile drop test method, while the surface profile of the laser textured surface was studied by using a 3D laser scanning confocal microscope. It is found that the use of the laser power above 25 W can produce surfaces with a water contact angle of more than 150° while increasing the laser scanning speed from 50 to 500 mm/s will cause the water contact angle to decrease by 16%.

The primary goal of this research is to investigate the effect of tribo-test parameters on the coefficient of friction (COF) and wear rate of the cylinder liner and piston ring pair. The tribological studies are carried out utilizing a full factorial design (FFD) experimental scheme. Sliding speed, temperature, volume concentration, and applied force were all evaluated as important parameters that determine tribological qualities. The effects of various variables and their interactions on the dependent variables were investigated. The ANOVA analysis demonstrates that the applied load could be the most influential factor affecting the minimum amount of the friction coefficient. The minimum quantity of wear rate indicates that as the sliding speed increases, the wear rate decreases.

When an infected person coughs, thousands of micro-size aerosol particles will transmit to the surrounding, especially in a closed space. Mosque is one of the confined areas that Muslims regularly go to pray together. Multiple standards of procedures have been proposed to prevent the virus transmission, however, the cases involving people praying in mosque are still reported. This study aims to simulate the virus transmission in mosque by modelling the aerosol particles generated by the worshipper coughing. A geometry of praying area in mosque was created mimicking the actual praying space. Realistic boundary conditions involving coughing, airflow at the inlet and outlet diffusers were specified. The simulation result confirms that the SARS-COV-2 virus in a closed space praying room is not uniform and it is strongly influenced by the location of the coughing source and the air conditioning layout. The study also recorded Ma’mums are at the higher chance to get infected if one of the Ma’mum is the COVID-19 carrier due to the nature of normal congregational praying arrangement. The outcomes of this study may help the scientist and the authorities to understand how dramatic COVID-19 virus may spread in the confined praying area, hence, may enforce a better standard of procedure in a mosque.

A tire serves various types of services and distance overs its lifespan. Moreover, for the safety and comfort of vehicle occupants, tire performance is critical. An assessment of literatures on tire-related properties that contribute to better safety performance was conducted in this study. The review elaborates on the most discussed topics from the overall reviewed articles. This study highlights the significant characteristics that be further implemented in tires for specific situations or general consumers. It was determined that tire wear is resulted from several factors. Increasing slip angles cause higher abrasion and temperature on tire surface. Modelling of wear rate can be done realistically with computation. From the review, it is also known that knowledge of tire-pavement and/or ice interactions behavior is improving. Semi-empirical methods in simulation of tire and terrain interactions are a promising candidate for use in multi-body dynamic software (MBS) simulation and vehicle simulations. Thermal aging in rubber tires will result in lower tensile strength. Production of tire wear particles increase 2–3 fold with abrasion from increased slip angles. Carbon back type N220 possess the best tensile, tear, and conductivity qualities. Overall, not much information was able to be obtained with regards to types of tires. Nonetheless research on tire safety performance should be extended so that each of tire component can be continuously improved to enhance tire safety criteria, particularly among the less discussed areas, such as commercial vehicle tires.

Carbon steel were used in various fields as it is economically affordable, environment friendly, highly durable and with high strength. However, carbon steel tends to corrode compared with other superior materials. Corrosion had brought negative effect to economic, health, safety, and also culture. One of the methods use in controlling the internal corrosion is by using the corrosion inhibitor. Inorganic corrosion inhibitor had long been used to suppress corrosion however they are toxic to health and also environment. Therefore, this research had been conducted to evaluate the potential of the corrosion inhibitor from palm oil leaves (POL) extract. The POL extract was extracted using Microwave Assisted Extraction method (MAE). After extraction, POL extract was sent to LC/MSQ-Tof analysis to test for active chemical component present. The presence of active component such as tannin, flavonoid and alkaloid help to inhibit corrosion. Corrosion inhibition testing were conducted by using weight loss method and electrochemical Tafel plot. SEM test show that carbon steel without inhibitor corrodes more than 90% compare with carbon steel coupon contain POL extract as an inhibitor.