Journal of Research and Applications in Mechanical Engineering

Metal 3D Printing - A Comprehensive Review on Materials, Methods and Properties

P. Amuthakkannan, V. Manikandan, K. Arunprasath — Tue, 16 Sep 2025 00:00:00 +0700

Metal 3D printing, which is also referred to as additive manufacturing (AM), encompasses a manufacturing technique that fabricates parts through the deposition of powder, wire, or sheets in a meticulous layer-by-layer fashion. Throughout the course of time, numerous methodologies have been devised to manufacture metal components by means of AM. The primary objective of this comprehensive review is to explore into the intricacies of metal 3D printing, including an examination of the advancements made in the realm of new materials tailored specifically for AM processes, as well as an exploration of the methods and properties of the materials printed.

Synthesis of FAME for Sustainable Aviation Fuel Based on Microwave Irradiation

Y. Wong, S. Matsunaga, N. Zhu — Tue, 16 Sep 2025 00:00:00 +0700

The need to reduce greenhouse gas emissions from the aviation industry has increased the search for alternative sustainable fuels. This study suggests a new method of using microwave irradiation to produce fatty acid methyl esters (FAME) based on esterification from waste cooking oil (WCO). FAME can be further converted into Sustainable Aviation Fuel (SAF) through hydrodeoxygenation and isomerization processes. In this study, we aimed to achieve a 95% synthesis ratio within 10 minutes by using microwave-assisted FAME synthesis from waste cooking oil. The research included pre-treatment and neutralization, followed by FAME synthesis under various conditions. FAME yield ratio was measured by GC method. Experimenta1 results showed that microwave irradiation could significantly reduce reaction time and energy use compared to traditional heating methods. The results confirmed that a 95% yield ratio was achieved within 10 minutes. This study highlights microwave-assisted FAME synthesis as a viable way to produce eco-friendly aviation fuels, helping to meet the aviation sector's sustainability goals.

Feasibility Assessment of PV and Energy Storage Systems for Nearly Zero Energy Office Buildings Using Generalized Reduced Gradient Method: A Case Study of Mae Moh Training Center EGAT

V. Prasitsuk, Y. Khunatorn, N. Lorpradit — Tue, 16 Sep 2025 00:00:00 +0700

This study evaluates the feasibility of implementing photovoltaic (PV) and energy storage systems to achieve Nearly Zero Energy Buildings (nZEBs) status for a cluster of buildings at the Mae Moh Training Center, Thailand. Using the Generalized Reduced Gradient method, three scenarios were analyzed: full-area installation, individual building optimization, and group optimization with energy storage. The full-area installation proved inefficient with only 24% PV utilization. Individual building optimization offered the shortest payback period of 3.17 years and 42% electricity reduction. Group optimization with energy storage emerged as the most comprehensive solution, achieving 75% PV utilization and 50% grid electricity reduction with an 8.67-year payback period for the optimal configuration of a 136 kW PV system and 100 kWh storage system. This approach best aligns with nZEB principles, offering balanced energy management and operational flexibility. The study demonstrates the potential of integrated PV and storage systems in achieving nZEB status.

Noise Prediction of Cylinder Flow using Machine Learning

N. Chinaso, K. Rattanamongkhonkun, W. Rojanaratanangkule — Tue, 16 Sep 2025 00:00:00 +0700

The accurate prediction of aerodynamic noise generated by cylinder flow is a critical challenge in various engineering applications, including automotive and aerospace industries. Traditional Computational Fluid Dynamics (CFD) methods, such as Direct Numerical Simulation (DNS), often require significant computational resources and time to simulate the complex interactions within flow. This study successfully creates a model using Machine Learning (ML) techniques to predict the pressure fluctuation in flow over a cylinder which provides a faster and equally reliable alternative to conventional methods.

Verification of Density Based Solver in OpenFOAM for High-Speed Inviscid Compressible Flow Analysis

P. Kamma, K. Loksupapaiboon, J. Phromjan, C. Suvanjumrat — Tue, 16 Sep 2025 00:00:00 +0700

Computational Fluid Dynamics (CFD) has become essential for modeling and analyzing high-speed compressible flows around complex geometries. However, the utility of this tool is compromised if it is unreliable. This study examines the performance of RhoCentralFoam, a density-based solver in the open-source CFD software OpenFOAM, which utilizes the Kurganov-Noelle-Petrova (KNP) central upwind scheme for numerical flux calculations. RhoCentralFoam was validated by comparing its results against reliable analytical solutions and experimental data across various Mach numbers (Ma). The solver demonstrated an average error margin of less than 2% and performed effectively within the determined Ma range, depending on the geometrical model. Furthermore, the Van Albada and SFCD schemes exhibited no significant differences and were implemented without inducing instabilities in shock wave simulations. These findings confirm that RhoCentralFoam is a reliable CFD tool for simulating high-speed compressible flow phenomena, offering significant potential for future research and practical applications.

Experimental Study of Air-Cooling System for Thermal Runaway Prevention of Nickel-Manganese-Cobalt Oxide (NMC) Battery Cells in Electric Vehicles

K. Hwaiwai, M. Masomtob, A. Kaewpradap — Tue, 16 Sep 2025 00:00:00 +0700

Battery thermal runaway (BTR) is a critical safety concern in electric vehicles (EVs), where heat generated within the battery can spread to adjacent cells, potentially causing explosions. This study investigates 18650-type NMC cylindrical cells to develop strategies for preventing battery fires linked to internal short circuits (ISCs) and self-heating, which can lead to BTR. We analyzed the impacts of battery surface temperature, blower speed, and cooling duration on preventing BTR. An air-cooling system was utilized to maintain surface temperatures at 90 ℃, 95 ℃ and 100 ℃, with air velocities at 1.92 m/s and cooling times of 5, 10, and 15 minutes. While BTR occurred with insufficient cooling time, cells cooled for at least 10 minutes at 90 ℃ and 95 ℃ showed no BTR signs. Importantly, at 100 ℃, no ISCs were observed after 15 minutes of cooling, demonstrating the effectiveness of proper cooling in preventing BTR.

Derivation of Positional Relation Matrix based on 3D Assembly CAD data: Disassembly Process Inference for Mechanical Products

K. Yamada, K. Takahashi, K. Hanahara — Tue, 16 Sep 2025 00:00:00 +0700

During machine maintenance, the disassembly task is more challenging than the assembly task because the disassembling process involves more patterns and possibilities than the assembling process, depending on the reasons or objectives of disassembling. In addition, an incorrect disassembly may cause machine damage or human operator injuries. Lists and instruction manuals of parts have been used for machine disassembly; however, these manuals cannot include all parts in general, and the disassembly of some parts is difficult for unskilled operators. Therefore, the disassembly process inference is crucial. In order to infer the disassembly process, a positional relation matrix consisting of the relative positional relationship between any two components is required to clarify the disassembly process. Currently, the matrix is derived manually; however, an automatic generation approach is required to reduce the computation effort. In this study, a method was developed to automatically generate a positional relation matrix based on the geometric information of machine part models, which can be obtained from three-dimensional assembly data of a computer-aided design. A case study was conducted using the proposed method, and it was confirmed that the method could generate positional relation matrix for disassembly.

Computational Fluid Dynamics Analysis of Fire Risks in COVID-19 Intensive Care Units: Assessing Oxygen Concentration, Ventilation Effectiveness, and Material Flammability in High-Risk Healthcare Environments

PK. Pant, S. Kothari, H. Verma, MK. Pathak, A. Joshi, S. Chamoli — Tue, 16 Sep 2025 00:00:00 +0700

This study examines the threats to fire safety in intensive care units (ICUs) during the COVID-19 pandemic, concentrating on ventilation effectiveness and oxygen concentration. Increased safety precautions are required in light of many deadly fires in intensive care units (ICUs), which were mostly brought on by electrical short circuits and made worse by elevated oxygen levels. Oxygen dispersion and concentration fluctuations were modeled in congested ICU rooms under various ventilation situations using Computational Fluid Dynamics (CFD) techniques. Important studies show that if ventilation systems fail, ICU rooms become high-risk zones in 6–10 minutes, with potentially catastrophic oxygen concentration levels. The study shows that natural ventilation is inadequate in critical care settings for controlling infection risks and oxygen levels. Oxygen distribution is greatly improved by increasing the number of mechanical ventilation points, which lowers fire risk. Furthermore, a number of textiles and polymers become combustible at oxygen concentrations between 24% and 35%, according to an analysis of the Limiting Oxygen Index (LOI) of popular ICU materials. In critical care settings, the study highlights the significance of appropriate ventilation design, reliable power backup systems, and cautious material selection. These results offer vital information for improving ICU fire safety procedures and safeguarding patients and medical staff in environments with high oxygen levels.

Comparison of High-Order WENO and TENO schemes for Shock Wave Capturing in Compressible-Fluid Simulation

M. Parnichprapa, P. Tunkeaw, W. Rojanaratanangkule — Tue, 16 Sep 2025 00:00:00 +0700

In this paper, the performance of high-order numerical schemes for capturing small-scale flow structures and shock waves is evaluated. The chosen schemes are a fifth-order WENO scheme of Jiang and Shu (1996) (WENO-JS), a sixth-order WENO with localized dissipative interpolation (CWENO6-CULD) of Wong and Lele (2017), and a sixth-order TENO scheme with adaptive dissipation of Fu, Hu, and Adams (2019). The results indicate that the CWENO6-CULD scheme offers reduced computational time than TENO6-A to 5%, while the TENO6-A scheme excels in capturing both small-scale flow features and shock waves with greater accuracy.

Many-Objective Optimization of Nonlinear Dynamic Inversion Altitude Controller Using Metaheuristics

N. Ruenruedeepan, N. Pholdee, N. Panagant, S. Bureerat — Tue, 16 Sep 2025 00:00:00 +0700

Effective control of nonlinear dynamics under varying conditions is challenging in aerospace systems, especially for altitude regulation. Traditional linear controllers like PID and LQR are simple but struggle with complex flight dynamics and changing conditions, such as airspeed and density variations. Nonlinear Dynamic Inversion (NDI) offers a solution by transforming nonlinear dynamics into a linearized form, allowing the use of linear control techniques. However, tuning NDI parameters is complex and time-consuming with traditional methods. Metaheuristic algorithms provide a robust alternative, efficiently exploring large solution spaces for near-optimal tuning. This study compares various metaheuristics for optimizing the parameters of NDI controllers in altitude control, assessing stability, responsiveness, and robustness. Results indicate that Success-History Based Adaptive Differential Evolution (SHADE) with Linear Population Size Reduction (L-SHADE) is the most effective algorithm for NDI controller optimization, delivering optimal control gains across varying conditions.

Effect of Titanium Dioxide Nanoparticles on Vapor Compression Refrigeration System Performance using R-410A Refrigerant and Polyolester Oil

D. P. Panchve, M. P. Ray , D. K. Dond, S. R. Suryawanshi — Tue, 16 Sep 2025 00:00:00 +0700

In this research, titanium dioxide nanoparticles were dispersed in polyolester oil to form a nanolubricant. The impact of this nanolubricant on the vapor compression refrigeration system performance, operating with R410A refrigerant was studied. The experimentation involved mixing different quantities of nanoparticles by mass into the POE lubricant. The quantities of TiO₂ nanoparticles used were 0.5% (1.221 g/L), and 1% (2.442 g/L) to create nanolubricant mixtures. A surfactant was added to prevent agglomeration. The refrigeration system functionality was compared using parameters such as the Coefficient of Performance (COP), refrigerating effect (RE), and compressor energy consumption. Several trial runs were conducted to obtain more accurate results and conclusions. It was observed that the refrigerating effect increased by 4.70% and 9.77% for nanoparticle concentrations of 0.5% and 1%, respectively, compared to plain lubricant oil without nanoparticles. No significant variation in compressor power consumption was observed for different nanolubricant concentrations. The COP of the system was enhanced by 4.72% and 9.47% for nanoparticle concentrations of 0.5% and 1%, respectively, compared to plain lubricant oil without nanoparticles.

In-plane Compression and Evolution Texture to Improve Drawability of Rolled AZ31B Magnesium-Alloy Sheets

M. Okawa, T. Murakami, T. Kuroki, A. Takasaki — Tue, 16 Sep 2025 00:00:00 +0700

Room-temperature forming of Mg alloy sheets is desirable over warm forming to mitigate machining hazards, lubricant degradation, and energy consumption. This study enhances the drawability of rolled Mg–3Al–1Zn (AZ31B) alloys at room temperature through in-plane compaction. Due to a limiting drawing ratio (LDR) below ~1.3, typical deep drawability parameters (n-value, r-value, tensile strength) could not be used. Instead, the activation of prism texture in surface sheets and the suppression of basal texture effectively accommodated thickness strain, improving drawability. In-plane pre-compression along angles relative to the rolling direction (RD) — 0° (RD), 30°, 45°, 60° and 90° (transverse directions, TDs) — with strains of 0.06 or 0.08 further enhanced formability. This process increased circumferential strain from 0.010 in as-received material to 0.227 in 6.0% pre-compressed specimens, demonstrating a significant improvement in room-temperature formability for AZ31B magnesium-alloy sheets.

Investigating PEMFC Performance with Dead-Ended Anode and Pressure Swing Technique under Dynamic Loading

Tue, 16 Sep 2025 00:00:00 +0700

The anode water management is a significant factor to mitigate local flooding and enhance performance at Proton Exchange Membrane Fuel Cells (PEMFC). The Dead-end anode (DEA) configuration operates dry hydrogen and utilizes a solenoid valve to seal the anode outlet. The Pressure Swing Technique (PST), based on the DEA configuration, generates periodic flow by adding more hydrogen via a solenoid valve between the inlet and outlet lines, rather than solely using a solenoid valve at the anode outlet. The hysteresis phenomenon, observed through dynamic voltage transients during forward and backward current sweeps, is applied in this study to investigate performance through voltage difference, voltage change, voltage decay rate, and voltage stability index under DEA and PST configurations in a single cell. The results indicated that PST improved stability by redistributing water within the anode channel but exhibited lower power density, specifically 5.46% less at a high current density of 400 mA cm^–2 due to insufficient membrane hydration. Additionally, longer purging intervals decreased cell output voltage while gradually enhancing stability for both configurations. Furthermore, slower switching period rates in PST leaded to instability.

A Shape Optimization Approach to the Design of a Cartilage Plate Used in Cartilage Tympanoplasty

Z. Wu, K. Okamoto, T. Shigeyoshi — Tue, 16 Sep 2025 00:00:00 +0700

This paper presents a shape optimization approach for a cartilage plate used in cartilage tympanoplasty to more closely approximate the original auditory characteristics of the human ear. First, we constructed a finite element model based on the geometric data of the middle ear, including the tympanic membrane, ossicles, and surrounding muscles. We then proposed a shape optimization method for designing the cartilage plate. The optimization problem was formulated with an objective function defined as the least squares difference between the amplitudes of the stapes post-repair and those in the healthy state across a wide frequency range. To enhance computational efficiency, we derived the shape gradient function and developed a method to calculate it using modal parameters. We employed the H¹ gradient method for shape modification. Finally, two numerical examples, using a combination of CAE software and a custom program, were conducted. In an idealized model, the objective function decreased by 98%, while in a repaired tympanic membrane model, it decreased by 43%, demonstrating the effectiveness of our approach.

Improvement of Spatial Resolution of W-BOS Analysis Images in Supersonic Flow Using Super-Resolution Technique

K. Maeda, H. Fukuoka, A. Suda, Y. Taniguchi, K. Hiro, S. Nakamura — Tue, 16 Sep 2025 00:00:00 +0700

The Wavelet-based Background Oriented Schlieren (W-BOS) method quantitatively evaluates the density gradient. This study achieves high spatial and temporal resolution in the density gradient images by integrating a super-resolution technique and the W-BOS method. This experiment uses a jet and a jet-induced shock wave emitted from an open small-volume shock tube as visualization targets. We investigated the effect of super-resolution model types and restoration magnification ratios. Three established super-resolution models are used to restore. The magnifications of 2, 4 and 8 are evaluated. At magnifications 2 and 4, the processed images were close to the original, with the shock wave and the jet well captured in all super-resolution models. In the restoration of magnification 4 using the EDSR model, a measurement error was about 15% smaller than a Bicubic interpolation. These results suggest that the W-BOS method is capable of super-resolution restoration of high-resolution images with magnifications up to 4.