SCOPE OF PUBLICATION The Journal of Transport System Engineering (JTSE) is a peer-reviewed, open access journal that publishes original research articles covering activity and development in the field of transport system engineering. This includes all aspects of the transport system including the infrastructure and vehicles as well as the associated services, components and equipment. The mode of transport includes land, rail, sea and air. JTSE is published online with a frequency of two (2) issues per year (June & December). Indexed by: Asian Science Citation Index, MyJurnal, MyCite, Google Scholar.
Copyright of articles that appear in Journal of Transpot System Engineering (JTSE) belongs exclusively to Penerbit Universiti Teknologi Malaysia (Penerbit UTM Press). This copyright covers the rights to reproduce the article, including reprints, electronic reproductions or any other reproductions of similar nature. Disclaimer: The views and opinions expressed in the articles are those of the authors and do not necessarily reflect the official policy or position of the JTSE. Examples of analysis performed within are only examples and they should not be utilized in real-world. Assumptions made within the analysis are not reflective of the position of any JTSE entities.
A COMPARATIVE ANALYSIS OF ENERGY CONSUMPTION AND CO2 EMISSIONS FOR ENERGY-EFFICIENT VEHICLES IN MALAYSIA
Malaysia’s road transport sector contributes significantly to national energy consumption and CO₂ emissions. This study develops a simplified comparative model to assess the operational energy use and CO₂ emissions of gasoline internal combustion engine vehicles (ICEVs), hybrid electric vehicles (HEVs), and electric vehicles (EVs) under Malaysian passenger-car conditions. Useful traction energy was estimated at 13.76%, 23.48%, and 69.19% for ICEVs, HEVs, and EVs, respectively. Compared with ICEVs, HEVs and EVs reduced annual operational CO₂ emissions by 38.69% and 45.96%, respectively, although EV performance remains strongly dependent on the electricity-generation mix. Scenario analysis indicates that electrification alone is unlikely to deliver rapid transport-sector decarbonisation without aggressive adoption, grid decarbonisation, and supporting infrastructure. HEVs and improved ICEV technologies can provide short- to medium-term transition benefits, while EVs offer stronger long-term potential with the expansion of renewable electricity, charging infrastructure, and clear policy support. The findings support a balanced transition strategy that combines electrification, vehicle efficiency improvements, and power-sector decarbonisation.
Copyright (c) 2026 Journal of Transport System Engineering
SURFACE ROUGHNESS EFFECTS ON SLENDER BODY AERODYNAMICS: A REVIEW FOR SCALED ROCKET APPLICATIONS
Surface roughness on rocket fuselage bodies has long been recognised as a factor in aerodynamic performance, yet how it specifically affects scaled rocket configurations is still not well understood. This paper reviews recent research on surface roughness effects in slender body aerodynamics, with a particular focus on scaled model rockets flying in the subsonic regime. The review covers four key areas: surface roughness characterisation and the equivalent sand-grain roughness; boundary layer transition mechanisms on cylindrical and slender bodies; quantitative drag and stability effects on complete vehicles; and how fuselage roughness influences centre of pressure and downstream flow behaviour. The findings show that roughness effects on slender bodies go well beyond skin-friction drag, modifying vortex asymmetry, control transition location, and alter the wake, all of which have stability implications. Current drag correlations carry ±11% uncertainty, and complete vehicle studies report drag increases of 17–75% for typical manufacturing roughness levels. Despite this body of work, a clear gap remains: no systematic study has isolated fuselage roughness effects on scaled rocket aerodynamic coefficients across a representative subsonic Mach and angle-of-attack envelope. This review lays the theoretical groundwork for such an investigation and highlights the need for design guidelines that connect measured surface finish to predicted aerodynamic behaviour in model rocketry.
AERODYNAMIC AND STRUCTURAL ANALYSIS OF COMPOSITE BLENDED WINGLETS FOR ALUDRA-EE UAV
Unmanned Aerial Vehicles (UAVs) commonly experience induced drag generated by wingtip vortices, which negatively affects aerodynamic efficiency and endurance. This study investigates the aerodynamic and structural performance of blended composite winglets for the ALUDRA-EE UAV using Computational Fluid Dynamics (CFD) and finite element analysis. Three winglet cant angle configurations (0°, 45°, and 60°) based on the RONCZ 1046 airfoil were evaluated using ANSYS Fluent to analyse lift, drag, lift-to-drag ratio, and vortex intensity. The aerodynamic results showed that the 60° blended winglet produced the best overall performance, achieving the highest lift-to-drag ratio of 22.23 and the lowest vortex intensity among all configurations. The optimized winglet configuration improved UAV range and endurance by approximately 26.14% and 41.7%, respectively. Structural analyses were subsequently conducted using Abaqus to evaluate hollow and solid composite winglet designs with different composite material configurations and ply orientations. The solid winglet constructed using standard carbon fibre fabric demonstrated the lowest displacement and failure indices while maintaining acceptable structural integrity under aerodynamic loading. The findings indicate that the proposed 60° composite blended winglet can significantly enhance the aerodynamic efficiency and structural performance of the ALUDRA-EE UAV.
LEARNING-BASED POSE ESTIMATION IN AUTONOMOUS ELECTRIC VEHICLE CHARGING SYSTEM USING ROBOT ARM MANIPULATION
Autonomous Electric Vehicles (AEVs) require fully automated charging systems to achieve complete autonomy. However, existing charging methods still depend on manual plug insertion by users. This study presents a learning-based control algorithm for autonomous robotic charging using a four-degrees-of-freedom robot arm. The robotic arm was designed in SOLIDWORKS, simulated in Gazebo, and controlled through the Robot Operating System (ROS). An object detection model was trained using a dataset of Type 2 EV charging sockets to identify the charging port, while a depth camera estimated its three-dimensional coordinates. The detected position was then processed by a motion planner to generate a collision-free trajectory for accurate plug alignment. Simulation results demonstrated reliable charging socket detection and robotic manipulation under various operating conditions. The proposed approach achieved a precision of 0.99 and a recall of 0.98, indicating robust detection performance. The highest detection confidence score of 0.87 was obtained at a charging socket distance of 1.1 m, while the lowest score of 0.73 was recorded at 1.0 m. These findings demonstrate the potential of the proposed framework for enabling reliable and autonomous EV charging operations.
NUMERICAL ANALYSIS OF THE AERODYNAMIC LIFT AND DRAG OVER SACCON UCAV
study numerically investigates the effect of leading-edge sweep angle on the aerodynamic performance of a generic Stability and Control Configuration (SACCON) unmanned combat aerial vehicle (UCAV). Three configurations with leading-edge sweep angles of 45°, 53°, and 60° were modelled and simulated using computational fluid dynamics (CFD) in ANSYS Fluent. A virtual wind-tunnel domain with a freestream velocity of 50 m/s was used, and the simulations were performed using the Spalart–Allmaras turbulence model at angles of attack of 5°, 10°, 15°, and 20°. The lift coefficient, drag coefficient, lift-to-drag ratio, and surface pressure distribution were evaluated for each configuration. The results show that the leading-edge sweep angle influences both lift and drag characteristics, particularly at higher angles of attack. The 53° reference configuration produced higher lift and drag at 20°, while the 45° configuration showed better lift-to-drag performance at higher angles of attack. The findings indicate that leading-edge sweep modification affects the aerodynamic efficiency of SACCON-type UCAV configurations and should be considered carefully in early-stage aerodynamic design.
AERODYNAMIC EFFECTS OF TRANSITION STRIP APPLICATION ON A MULDICON WING IN LOW-SPEED WIND TUNNEL TESTING
Low-sweep, blunt-leading-edge unmanned combat aerial vehicle (UCAV) configurations exhibit complex vortex separation and inconsistent aerodynamic behaviour at moderate-to-high pitch angles. This study experimentally investigates the effects of leading-edge transition strips on a lambda-planform MULDICON AVT251 wing with a 53° blunt leading-edge sweep. Wind-tunnel tests were conducted in the UTM Low-Speed Wind Tunnel at Reynolds numbers of 3.00×105 to 4.50×105 and pitch angles from −4∘ to 30∘. Lift, drag, pitching-moment coefficients, and surface flow visualisation were analysed for free-transition, 2D-transition, and 3D-transition cases. The results show that transition-strip type strongly affects the onset and progression of leading-edge vortex separation. For the 3D transition case, stall occurred at a=24∘, with CL=1.0183, while Cm remained more predictable up to a=22∘. The findings indicate that the pitching-moment coefficient is highly sensitive to flow topology and vortex-separation behaviour. Overall, the 3D transition strip is recommended to establish a repeatable baseline for future MULDICON flow-field measurements and CFD validation at subsonic.
TEMPERATURE-DEPENDENT SURFACE ENERGY AND WETTABILITY OF POLYALPHAOLEFIN WITH ORGANIC FRICTION MODIFIERS
This study investigates the temperature-dependent wettability and surface energy behaviour of polyalphaolefin (PAO4) lubricants modified with renewable organic friction modifiers, namely fatty acid methyl ester (FAME) and glyceryl monooleate (GMO). While PAO exhibits excellent thermal stability, its inherently low polarity limits surface interaction and may reduce its effectiveness under boundary-dominated lubrication conditions. To address this limitation, PAO4 was blended with varying concentrations of FAME and GMO, and their interfacial behaviour was evaluated on steel and glass substrates at 25°C, 40°C, and 60°C using contact angle measurements. The results show that increasing additive concentration consistently reduces contact angle and interfacial energy, accompanied by reduced interfacial energy and improved spreading behaviour. On steel surfaces, the contact angle decreased from 34.21° for neat PAO4 to 19.71° for the PAO4–FAME 10 wt% blend at 60°C, corresponding to approximately 42% improvement in wettability. Similarly, PAO4 blended with GMO 7 wt% exhibited the lowest interfacial energy among the tested formulations. FAME (10 wt%) and GMO (7 wt%) exhibited optimal performance, indicating a concentration-dependent balance between polar interaction and dispersive spreading. Temperature further amplifies these effects, suggesting thermally activated molecular mobility enhances surface affinity. These findings demonstrate that wettability enhancement in PAO-based lubricants is governed by the interplay between additive polarity and temperature, providing a practical framework for screening sustainable friction modifiers. The study offers a surface-energy-based approach for screening lubricant–surface compatibility as a preliminary indicator for boundary lubrication applications.
TRIBOLOGICAL APPLICATIONS OF PROTIC IONIC LIQUIDS: EFFECTS OF IONIC STRUCTURE, CHALLENGES, AND FUTURE PERSPECTIVES
Protic ionic liquids (PILs) have emerged as promising candidates for advanced lubrication owing to their intrinsic thermal stability, negligible volatility, and ability to form protective boundary layers at sliding inter faces. This review revealed ionic species present with long alkyl group, or specialised functional group that enhanced intermolecular interaction which tend to improves tribological ability, thermal stability and raise viscosity. Additionally, the compatibility of PIL with base oils is critical for effective additive performance, as insufficient miscibility limits ion transport and interfacial coverage. Hydrolytic stability is another critical concern for application in high-moisture environment which are rarely examined in literature. Collectively, the current findings highlight the need for integrated molecular design strategies that simultaneously consider chain length, ion-pair chemistry, oil compatibility and hydrolytic stability, to realize the full potential of PILs as tunable, high-performance lubricants or additives.
TRANSIENT SIMULATION AND PERFORMANCE ANALYSIS OF NOVEL EVAPORATOR FOR OTEC APPLICATION
cean Thermal Energy Conversion (OTEC) harnesses the temperature difference between warm surface seawater and cold deep seawater to generate electricity. The evaporator, a key component, facilitates heat absorption and phase change in the working fluid. This study presents a transient simulation and performance analysis of a novel evaporator design for OTEC, aiming to enhance heat transfer efficiency while minimizing pressure drop. A computational fluid dynamics (CFD) model was developed using ANSYS Fluent, incorporating various mass flow rates and turbulence models. The k-omega SST model proved most effective in capturing phase change dynamics. Results show the proposed design absorbs 2 kW more thermal energy than conventional designs at scale, with an optimal flow rate of 0.01856 kg/s balancing energy absorption and pressure constraints. The maximum pressure drop was 6.19 kPa for R-22, significantly lower than traditional heat exchangers. The design improves heat transfer and reduces energy losses, enhancing OTEC system efficiency. Turbulence-enhancing modifications at the inlet were identified to further accelerate phase change without excessive pressure penalties. These advancements support more efficient Rankine cycle implementations, improving OTEC feasibility and scalability. This study contributes to the development of high-performance heat exchangers, advancing OTEC as a sustainable energy solution.
Copyright (c) 2025 Journal of Transport System Engineering
FUEL USAGE TRENDS AND INVENTORY FOR MALAYSIA ROAD TRANSPORT SECTOR
The shift towards sustainable transport in Malaysia demands a clear understanding of the environmental performance, trends, and status of major fuels in use. This study compiles and compares existing Life Cycle Inventory (LCI) data for key transport fuels such as petrol, natural gas, and coal-derived fuels, alongside an analysis of their production, consumption, and trade trends. Secondary data are gathered from national statistics, trade records, published literature, and environmental databases to assess energy use, emissions, and resource flows across the fuel life cycle. The compiled information provides an up-to-date overview of Malaysia’s transport fuel landscape, serving as a reference for evaluating life cycle impact assessment, energy analysis, and potential transition pathways toward low-carbon mobility.
THE EFFECT OF DIMPLE DEPTH TO THE FRICTION AND WEAR IN LINEAR MOTION
Friction and wear remain major contributors to energy loss in engineering systems, demanding optimized surface engineering strategies. This study examines the effect of dimple aspect ratio on the tribological behavior of aluminium alloy surfaces textured using Laser Surface Texturing (LST). Elliptical dimples with depths of 100 µm, 150 µm, and 200 µm were fabricated and tested under lubricated linear reciprocating motion. Results show that the 150 µm dimples achieved the lowest coefficient of friction (COF), with reductions of 20.5%, 26.2%, and 5.0% compared to untextured surfaces at 40 N, 50 N, and 60 N, respectively. Wear analysis revealed that the 150 µm geometry reduced scar length by 21–28% relative to deeper textures, while maintaining balanced performance across all loads. Surface roughness (Ra ≈ 0.095 µm) confirmed its optimal lubrication-retention capability. Overall, the findings establish that intermediate aspect ratios maximize lubrication stability, reduce direct asperity contact, and improve component reliability for energy-efficient applications.
EXPERIMENTAL STUDY ON LOW-SPEED VERTICAL AXIS CURRENT TURBINE (LS-VACT) WITH DIVERTER
The increasing demand for sustainable energy solutions has intensified the exploration of marine current energy systems in low-speed current regions such as those found in Malaysia. This study investigates the performance enhancement of a Low-Speed Vertical Axis Current Turbine (LS-VACT) through the integration of a curved shape diverter. The primary objective is to evaluate the diverter's effect on power coefficient (Cp), torque coefficient (Ct) and efficiency under controlled towing tank conditions at current speed of 0.4 m/s. Two configurations were tested; the LS-VACT arm attached turbine with and without curved diverter angled at 30°. The turbine with diverter achieved an enhancement for the maximum Cp, reaching up to 50% increase over the baseline at TSR 0.55 while maintaining favourable torque generation and improved TSR across different RPM. The diverter improved flow interaction with the advancing blade. The findings validate the application of curved shape diverters as a practical and passive method to improve LS-VACT performance in low-speed marine environments.
THE PREDICTION MODEL FOR ELECTRIC VEHICLES ADOPTION RATE IN MALAYSIA
This comprehensive study presents an integrated analysis of electric vehicle (EV) adoption in Malaysia, combining behavioural research, advanced predictive modelling, and policy assessment to evaluate the country's readiness for sustainable transportation transition. The research employed a sequential mixed-methods approach, integrating a validated Theory of Planned Behaviour (TPB) survey with hybrid forecasting models to assess current adoption trends and project future scenarios through 2030. A two-phase TPB survey was conducted with a pilot test (n=50) and main survey (n=500), achieving excellent reliability across all constructs (Cronbach's α = 0.802-0.850). Advanced modelling framework combining SARIMAX, LSTM, and weighted ensemble approaches achieved excellent predictive accuracy at the national level (R² = 0.822). Key findings reveal that while Malaysia's EV market demonstrated 45.6% growth in Q1 2025, reaching 6,827 units, no region is projected to meet the 20% 2030 adoption target under current trajectories. Current infrastructure deployment stands at 4,161 charging stations, representing 41.6% progress toward 2025 targets. Behavioral analysis indicates perceived behavioral control as the primary barrier despite positive consumer attitudes. Strategic recommendations include accelerating rural charging infrastructure, extending fiscal incentives beyond 2025, and implementing targeted behavioural interventions.
OPTIMIZATION OF HORIZONTAL AXIS WIND TURBINE DESIGN AND PERFORMANCE IN ARRAY ARRANGEMENT FOR MALAYSIAN SEAS
Malaysia offshore regions have the potential for the development of the Horizontal Axis Wind Turbine (HAWT) wind turbine, where the annual mean wind speed is greater than 4 m/s. Although the annual wind speed meets the minimum requirement for wind turbines to generate electricity, the steady wind flow is still lower compared to other countries. Therefore, the purpose of this paper is to optimize the parameters of the wind turbine blades to improve the performance and power production of HAWT for the usage in Malaysian sea. The performance and power production of optimized turbines in array arrangement is also investigated. Computational analysis using software Qblade was performed to evaluate the result of power production of blade properties including blade diameter and blade angle of attack, while Computation Fluid Dynamic (CFD) is used to evaluate the performance in array arrangement when subjected to Malaysia sea conditions. Results show that a wind turbine blade with a diameter of 150m and blade angle of attack of 6 degrees has the better performance in the variation of wind speed. In staggered wind farm configuration, the estimated total power output of 20450.83 kW is expected to be obtained by 6 units of turbines.
Friction and Wear Performance of Lubricants Formulated with Palm Kernel Methyl Ester and Polymeric Additives in Hydrogen-Fuelled Engines
The transition to sustainable fuels and lubricants is critical in supporting the advancement of hydrogen internal combustion engines (H₂ICEs). Bio-lubricants derived from vegetable oils, such as palm kernel methyl ester (PKME), offer environmental advantages including renewability, biodegradability, and high lubricity. However, their inherently low viscosity poses challenges in demanding engine applications. This study investigates the use of ethylene-vinyl acetate (EVA) copolymer as a viscosity index improver (VII) in PKME-based lubricants for potential use in H₂ICEs. Tribological performance was evaluated using a four-ball tribotester and a modified pin-on-disc tester at varying EVA concentrations (2–4%), loads, and temperatures. The addition of 4% EVA enhanced the viscosity index of PKME by 61% and improved friction-reducing capabilities compared to SAE 40 mineral oil. While wear resistance remains slightly inferior, the frictional improvements indicate promising potential for PKME-EVA blends in hydrogen engine lubrication. Further formulation optimization is recommended to enhance anti-wear performance for reliable H₂ICE operation.
Effect of Worn Top Compression Ring and Lubricant Degradation Towards Engine In-Cylinder Frictional Losses
Friction occurs in the internal combustion engine especially at the interface between piston ring and cylinder liner. This causes an increase in fuel consumption required to overcome these frictional losses. Piston ring-cylinder interface is one of the primary sources. This study is imperative to understand the effects of lubrication degradation and worn top compression ring towards engine frictional losses. A mathematical model with the integration of 1-D Reynold’s equation is derived to investigate the lubrication film and pressure generation. This study further incorporates velocity, surface roughness, combustion pressure, lubrication degradation and presence of worn top compression ring to demonstrate the frictional losses. It was found that lubrication degradation significantly affects the lubrication film formation, impacting friction at the piston ring-cylinder liner interface. Increased lubricant viscosity increases viscous friction while reducing boundary friction. Similarly, a worn top compression ring leads to higher viscous friction due to a thicker film and larger load-bearing area, decreasing boundary friction. It is concluded that both lubrication degradation and worn top compression rings have detrimental effects on frictional power losses.
Influence of Organic Friction Modifiers on Surface Energy Properties in Polyalphaolefin (PAO) Blends
The shift towards alternative fuels like hydrogen, ethanol, and other sustainable energy sources drives the need for high-performance lubricants to handle new thermal and chemical challenges. Synthetic polyalphaolefins (PAOs) are commonly utilised due to their thermal stability, high viscosity index, and reliable low-temperature flow. This study investigates the impact of organic friction modifiers—oleic acid (OA) and stearic acid (SA)—on PAO-based lubricants' tribological and interfacial characteristics. Blends containing 0.1–0.5 wt% OA or SA were tested. Contact angle measurements indicated that the 0.3 wt% OA blend significantly improved surface wettability, achieving the lowest contact angles on glass and steel surfaces. Surface energy analysis revealed decreased surface tension and better adhesion for the 0.3 wt% OA blend. Friction testing showed that the 0.3 wt% OA blend recorded the lowest coefficient of friction; however, wear resistance largely remained unaffected. These findings indicate that OA improves frictional performance in PAO lubricants, presenting a promising avenue for optimising formulations for future energy systems.
Modelling of Bearing Lubrication for Electric Vehicle Motor Bearing
Bearing failure in electric motors is increasingly attributed to complex electro-thermal interactions that accelerate surface damage and lubricant degradation. Electrical current discharge disrupts the lubricant’s rheological properties, diminishing film thickness and undermining protection in the elastohydrodynamic lubrication regime. This study presents a numerical model that integrates EHL theory with heat generation from shear and electrical sources while capturing the influence of key operating parameters such as shaft speed, bearing resistivity, and temperature. The findings reveal that current discharge markedly reduces minimum film thickness and distorts pressure distribution due to localised temperature rise and viscosity breakdown. The model demonstrates strong predictive capability by capturing the coupled effects of entrainment, rheological degradation, and electro-thermal loading. These results underscore the sensitivity of EHL film formation to electrical stress and highlight potential failure thresholds under realistic operating conditions. The insights gained can inform the development of advanced bearing systems with enhanced thermal management, electrical insulation, and lubricant formulation strategies, ultimately improving the durability and reliability of electric motor drivetrains.
IMPACT OF RIGID WALL BACK SHAPE ON THE SOUND ABSORPTION PERFORMANCE OF MICROPERFORATED PANELS
Microperforated panels (MPPs) are promising sound absorbers with significant potential for enhanced performance. Numerous studies have explored ways to improve MPPs by adjusting parameters such as perforation ratio, perforation diameter, panel thickness, air gap thickness, and material choice. Typically, MPPs are installed in front of rigid, flat surfaces; however, the effect of wall shape has been largely unexplored. This study investigates the impact of three different wall shapes—flat, stair-shaped, and concave—on MPP sound absorption. Both MPPs and models of the three wall shapes were 3D-printed, and their sound absorption was evaluated using an impedance tube. The results show that stair-shaped and concave walls provide superior sound absorption, particularly in the low-frequency range, compared to flat walls with the same air gap distance. These findings suggest that non-flat wall designs, such as stair-shaped and concave, can enhance sound absorption at lower frequencies. This study highlights the potential for MPPs to be effectively installed in front of rigid walls or surfaces of various shapes, expanding their applicability across a wide range of acoustic environments.
Copyright (c) 2024 Journal of Transport System Engineering
DESIGN AND PERFORMANCE ANALYSIS OF EXPANDER FOR WASTE HEAT RECOVERY APPLICATION
Waste heat recovery (WHR) is one of the solutions for net zero carbon and decarbonization activity. Currently, the Organic Rankine Cycle is widely studied because of its capability to operate at a wide range of temperatures, scalability, lower operating temperature, and high thermal efficiency. Despite advancements, challenges in expander design and performance analysis limit waste heat recovery. Therefore, the objective is to design and analyse a suitable expander for waste heat recovery and achieve a total-to-total efficiency exceeding 70% with a minimum power output of 30kW at a pressure ratio of 1.4. The design and performance analysis for 3D blade geometry and expander using the ANSYS CFX software. An applied meanline modelling was conducted using MATLAB. The results demonstrated the expander's capability to generate 35.857 kW of power, exceeding the design target. Additionally, a total-to-total efficiency of 74.69% was achieved, surpassing the minimum efficiency threshold of 70%, even after accounting for tip leakage losses. The findings contribute valuable insights for optimizing expander designs and advancing waste heat recovery technologies aligning with global efforts to promote sustainable energy systems.
COMPUTATIONAL FLUID DYNAMICS ANALYSIS OF NEW CONCEPT HEAT EXCHANGER FOR OTEC APPLICATION
This paper presents a comprehensive analysis of a new concept of heat exchanger for Ocean Thermal Energy Conversion (OTEC) applications. The study utilizes Computational Fluid Dynamics (CFD) simulations to evaluate the performance of different heat exchanger designs for extracting thermal energy from oceanic sources, specifically using water and R717 liquid. Key performance parameters including cold vapor fraction, temperature difference, and pressure drop are evaluated through a combination of numerical simulations and experimental validations. The analysis of the cold vapor fraction provides insights into evaporation rates and their distribution across multiple prototypes, highlighting the impact of the wetted area on heat transfer effectiveness. The evaluation of temperature differences reveals variations in discharge fluid temperatures, with some prototypes deviating from thermodynamic principles at a default evaporation frequency of 0.1. Various evaporation frequencies are simulated and compared with experimental data to select the optimal frequency for each prototype. The simulations and experiments, conducted under similar conditions, ensure accurate validation despite inconsistencies arising from variations in heat exchanger design and boundary conditions. The performance evaluation demonstrates the effectiveness of the three prototypes, with Prototype 2 achieving the highest effectiveness up to 59% for OTEC applications. The findings contribute to a better understanding of heat exchanger performance in OTEC and provide valuable insights for design optimization and future application development. This paper emphasizes the significance of efficient heat transfer and highlights the potential of ocean thermal energy as a renewable and sustainable resource.
DESIGN AND DEVELOPMENT OF THREE-DEGREES-OF-FREEDOM ROBOTIC ARM FOR ELECTRIC VEHICLE CHARGING STATION
The exponential growth of the electric vehicle (EV) industry requires the development of more efficient and easily accessible charging infrastructures. The existing manual charging procedures provide significant difficulties, especially for those with impairments. The objective of this project was to overcome these difficulties by designing and developing a robotic arm that is particularly designed for automating the process of charging electric vehicles. The project aimed to improve operational efficiency and user accessibility by designing a three-degrees-of-freedom robotic arm using CAD software, SOLIDWORKS, and prototyping it using 3D printing technology. The main approaches employed were thorough Finite Element Analysis (FEA) to guarantee the structural integrity to confirm the operational dependability. The primary results indicate that the robotic arm design successfully automates the charging process, resulting in a substantial reduction in the human labor needed from users and an improvement in the accuracy of the charging connection. These results not only showcase the arm's capacity to completely transform EV charging methods but also emphasize its flexibility in different vehicle settings, indicating a wide range of possible uses in automated systems in the future.
EVALUATION OF AUTONOMOUS NAVIGATION AND PATH ACCURACY FOR UNMANNED SURFACE VEHICLES USING IMU SENSOR AND GPS DATA
The development of autonomous systems for environmental monitoring is becoming increasingly important. This project focuses on creating a robotic marine vessel, Aqua Sense, for efficient water quality monitoring. Existing methods are often labour-intensive, time-consuming, and lack real-time data capability. The objective is to develop a robotic vessel with autonomous navigation for water quality applications. A comprehensive design approach, including a literature review and careful component selection, was employed. Key components include the Arduino Mega, Blue Robotics T200 thruster, GlobalSat BU-353N5 GPS sensor, BNO055 Inertial Measurement Unit (IMU), and a Li-po 11.1v battery. In this paper, several field trials data collection is presented to evaluate the navigation algorithm. These findings validate the feasibility of Aqua Sense for real-world applications. The varying distance errors at points B and C demonstrate an error range, with a maximum error of approximately 1.130m at point B (about 0.11% of the target location) and a significant variation at point C, reaching up to 1.660m (approximately 0.15%).
INVESTIGATING THE INFLUENCE OF PROTIC IONIC LIQUID ON THE TRIBOELECTRICAL PROPERTIES OF TRIMETHYLOLPROPANE TRIOLEATE (TMPO)
Under triboelectric conditions, where tribocharging accelerates lubrication failure, lubricants with enhanced electrical properties are essential. Trimethylolpropane Trioleate (TMPO) oil, derived from esters that possess good lubricating properties and wear performance but is lacking in terms of electrical properties which can be further improved when blended with Ionic Liquid. This study blends 1 – 5 wt% of Protic Ionic Liquid (PIL) into TMPO and evaluate the frictional and wear performances of the blends under 1 – 2 A current conditions to understand the behaviour towards the tribological properties of different blends of material. Electric currents ranging around 1 – 2 A are implemented to the custom-designed ball-on-disc tribometer, with a constant 4.5 V voltage supply and the static resistance are measured. Mechanical wear properties are observed after the tribological test with different samples. The frictional properties of all concentrations of PIL in TMPO showed significant frictional improvements with 1%wt PIL showed 53% better results indicating improvements in frictional properties and wear performance under 2A current conditions, owing to its lowest film resistivity of 0.14 mΩ.
INVESTIGATION OF WIND FLOW CHARACTERISTICS USING PASSIVE DEVICES IN BOUNDARY LAYER WIND TUNNEL
Atmospheric boundary layer (ABL) flow can be generated in an open-loop boundary layer wind tunnel (BLWT) to simulate a realistic rough-wall condition imposed on the natural wind. An open-loop BLWT experiment is performed in this work using a wall barrier and roughness elements as passive devices to create a rough-wall condition and reproduce a realistic neutral ABL flow. The roughness elements used are homogeneous cubic blocks with a side length of 25 mm arranged in a staggered layout at 12.5% packing density. Wind velocity data is measured in the upstream test section of the BLWT using a hot-wire anemometer (HWA) to obtain the wind velocity profiles, i.e., mean wind velocity, standard deviation, and skewness. The height z was measured from z = 7 mm from the test section floor to z = 800 mm. The mean vertical velocity profile of the rough wall indicates a significant decrease within the height interval of z/zref < 1.0 due to the surface roughness. Additionally, the normalized mean wind velocity is approaching unity at z/zref = 1 with the rough wall, whereas the smooth wall (no roughness elements) is observed at z/zref = 0.1. Moreover, the standard deviation profile of the rough wall shows higher values in the near-wall region (z/zref ≤ 0.4), suggesting a higher level of turbulence in the wind flow due to surface roughness. Finally, the rough wall skewness profile is left-skewed, suggesting a non-Gaussian feature. The study found that roughness parameters affect vertical velocity profiles and create realistic atmospheric boundary layer flows.
ASSESSING THE TRIBOLOGICAL PERFORMANCE OF POLYALPHAOLEFIN UNDER ELECTRICAL CURRENT CONDITIONS
Polyalphaolefin (PAO) lubricants have long been a staple in the aviation industry, prized for their exceptional friction-reduction properties in high-temperature environments. However, as the industry embraces electrification to decarbonise passenger planes, the demand for suitable lubricants to accommodate the extreme working conditions of electric motors has surged. Understanding how these lubricants perform under electrical conditions becomes crucial, particularly by delving into the frictional characteristics when exposed to electrical current. This study explores the frictional behaviour of PAO4, a specific type of PAO lubricant when subjected to electrical working conditions. It is to conclude that the frictional performance of PAO4 decreases subject to electrical current discharge, with the friction increasing around 30% with an additional temperature increment of 15%. Thus, the investigation aims to understand the interplay between friction and electrical current within the evolving aviation industry.
COMPARATIVE STUDY OF ELECTRICALLY AND INDUCTIVELY ACTUATED SHAPE MEMORY ALLOY NITI WIRE USING TENSILE TESTING
Shape memory alloy (SMA) actuators have the capability to actuate high forces while being compact, making them a potential replacement for complex electromechanical systems especially in aerospace applications. Common heating technique of SMA actuator is electrical heating. However, the actuation capability of SMA is dependent on the heat transfer mechanism of SMA as it is very sensitive to temperature and stress, thus lead to the difficulty in controlling mechanism. Owing to the complex controllability of heating techniques, the induction heating technique for SMA wire was undertaken in this investigation and proposed to be promising technique for SMA. A comparison between electrical heating and induction heating were performed using tensile testing. The tensile loading was performed using Instron 3366 Universal Testing Machine (UTS) with a 5 kN load cell and strain rate of 0.04 mm/min. A series of experiment at three different activation temperatures of 60°C,70°C and 80°C were performed for both the electrical and induction heating technique. The electrical actuation was done through power supply, whereas the inductive actuation was done through a specially developed heat control chamber comprises electromagnetic coil. The stress-strain curve for loading path was developed for both techniques and were compared. The results showed that the loading profile for inductively actuated wire was similar to the loading pattern of SMA superelasticity performance compared to electrical actuated wire which was nonlinear and serrated. In conclusion, induction heating technique is seemed to be a promising method to actuate SMA precisely.
ADVANCEMENTS IN SUPERSONIC FLIGHT CONTROL: REVIEW OF CAVITY FLOW IMPACT AND INTEGRATION OF ACTIVE AND PASSIVE CONTROL MECHANISMS
This review paper explores the challenges of supersonic flight, specifically focusing on the impact of cavities on flight dynamics and the effectiveness of various control mechanisms. The paper addresses three primary objectives: understanding cavity-induced effects during supersonic flight, evaluating the effectiveness of active and passive cavity flow control techniques, and exploring the integration of both approaches for optimized control. Cavities, or recessed areas on aircraft surfaces, can cause complex shock-wave patterns during supersonic flight, leading to problems like increased drag, reduced controllability, and heightened acoustic emissions. The paper aims to highlight the the mechanisms underlying these cavity-induced phenomena by analyzing existing research and shedding light on their effects on flight dynamics. The effectiveness of two distinct control strategies, active and passive, in managing cavity-related issues is investigated. Active control involves real-time adjustments using technologies like jets and feedback loops, while passive methods alter flow behavior through design features. The review examines the outcomes of research studies that have employed these techniques, providing an assessment of their individual merits and limitations. The paper also emphasizes the potential benefits of integrating active and passive control approaches to achieve a comprehensive solution for cavity-induced instabilities. By combining the strengths of both methods, this integrated approach promises improved stability, reduced drag, and enhanced overall flight performance. The review synthesizes findings from existing research, facilitating a comparison of outcomes, and offering a guide for future investigations into the synergistic application of active and passive controllers.
EXPERIMENTAL EVALUATION ON THE EFFECTS OF ENERGETIC ADDITIVES IN THE HYBRID ROCKET FUEL
This paper evaluates the viability of employing paraffin wax including energetic additives as solid fuel in a hybrid rocket. In this paper, three distinct fuel compositions were used to compare the augmentation of the regression rate. Hybrid rockets combine the best characteristics of solid and liquid rockets, and they provide a multitude of advantages, such as safe handling and storage, a wider variety of fuel, a lower price, and enhanced dependability. However, it has a key drawback that hinders performance: a low regression rate. An earlier study found that doping the fuel with energetic additives such as aluminium, boron, hydrogen, and ammonia might increase the pace of regression. These nanoparticles will enhance evaporation and combustion efficiency, hence accelerating regression. According to the data, using aluminium increases regression rates by up to 21.2%, followed by using magnesium (19.9%), and iron (8.7%), which has the smallest increase in regression rates. According to this study, adding energetic materials to the fuel of hybrid rocket motors has improved the regression rate problem.
EFFECTS OF BUILDING INTERFERENCE ON A GENERIC BUILDING MODEL
The presence of nearby buildings would alter wind flow patterns around the existing building and may lead to interference effects. In previous studies, detailed explanations on the interference effects between buildings are not well explained. Thus, the purpose of this study is to investigate the interference effect, particularly the effect of different height ratios of the interfering building and different wind incident angles. The experiment was conducted in the UTM-LST wind tunnel where surface pressure was measured on both of the wall and the roof of the target building of a generic building model. Based on the result obtained, the interference factor, IF for the South Wall B were 0.9, 0.6, and 0.2 for interference height 0.3H, 0.6H, and H respectively. These values represent a reduction of wind load on the building façade where the highest was an 80% reduction. On the roof, the IF obtained were 1.4, 0.9, and -0.2 for interference heights of 0.3H, 0.6H, and H respectively. The suction load was increased by 40% for interference height of 0.3H and decreased by 20% and 120% for interference height of 0.6H and H.