Now showing 1 - 6 of 6
  • Publication
    Numerical investigation of immersion cooling performance for Lithium-ion polymer (LiPo) battery: effects of dielectric fluids and flow velocity
    (IOP Publishing, 2023)
    A Z A Akmal
    ;
    Muhammad Faiz Hilmi Rani
    ;
    Wong Keng Yinn
    ;
    Mohd Ibthisham Ardani
    ;
    ; ; ;
    M S A Kadir
    ;
    Rishan Murali
    ;
    Sukport Sunan
    This study investigates the enhancement of immersion cooling performance for a single 14.6 Ah lithium-ion polymer (LiPo) battery cell by using air, palm oil, and engineered fluid (3M Novec 7000) as dielectric fluids. The research aims to observe the temperature distribution and rate of heat transfer on the battery cell at a 3C discharge rate, while varying the fluid velocity flow (0 mm/s, 1 mm/s, and 50 mm/s) and fluid types. Computational fluid dynamics (CFD) simulations were performed using ANSYS Fluent software, with heat generation from the LiPo battery simulated using the Newman, Tiedmann, Gu, and Kim (NTGK) semi-empirical electrochemical model. Results revealed that palm oil demonstrated the optimum cooling effect, reducing peak temperature to safe operating temperature region by 62.4% within 1020 seconds. Fluid flow velocity strongly influenced temperature distribution and heat transfer rates, with 50 mm/s resulting in a more uniform temperature distribution compared to 1 mm/s and 0 mm/s. The rate of heat transfer was highest at 1 mm/s and intermediate at 50 mm/s. Considering the abundance of palm oil in Malaysia, utilizing it as the dielectric fluid with a 50 mm/s flow velocity yields the best cooling effect for the 14.6 Ah LiPo battery at a 3C discharge rate.
  • Publication
    Impact of intake manifold geometry on power and torque: a simulation-based study
    (Semarak Ilmu Publishing, 2025)
    Muhammad Hussein Akbar Ali
    ;
    ; ;
    Eswanto
    ;
    Naoki Maruyama
    ;
    Girrimuniswar Ramasamy
    ;
    ;
    Rishan Murali
    ;
    Azizul Aziz Ishak
    ;
    Muhammad Faiz Hilmi Rani
    The internal combustion engine (ICE) remains pivotal in motorcycle technology, primarily due to its efficiency, energy density, and established infrastructure, despite the rise of electric vehicles. This study examines the influence of intake manifold design parameters on the performance of a single-cylinder internal combustion engine (ICE), with a specific focus on brake power and brake torque at high engine speeds. A comprehensive parametric analysis was conducted using a 1D simulation model in Ricardo Wave, evaluating the effects of manifold length, diameter, and bending angle on engine performance metrics. The results demonstrate that the optimized intake manifold design yields a 7.75% improvement in brake power and a 6.5% enhancement in brake torque at 10,000 RPM compared to the baseline configuration. Mid-range values for manifold length and diameter were found to achieve optimal airflow dynamics, effectively minimizing pressure losses. Additionally, a bending angle of 70° exhibited superior stability in power delivery at elevated engine speeds. These findings underscore the critical role of intake manifold geometry optimization in achieving enhanced engine performance under high-speed operating conditions.
  • Publication
    Analysis of temperature and relative humidity distributions in a dental treatment room at a government health clinic in Malaysia
    (Semarak Ilmu Publishing, 2025)
    Mohamad Nazrin Yahaya
    ;
    ;
    Eswanto Eswanto
    ;
    Naoki Maruyama
    ;
    ; ; ;
    Muhammad Faiz Hilmi Rani
    This study investigates the vertical distribution of temperature and relative humidity within dental treatment rooms at a Government Type 3 Health Clinic in Gial Perlis, Malaysia, addressing a significant gap in the literature regarding environmental conditions in dental healthcare settings. Precise measurements were conducted at four specific heights 0.3 m, 1.0 m, 1.7 m, and 2.7 m utilizing calibrated digital thermometers with hygrometers to capture accurate environmental data. The collected data were analysed using Analysis of Variance (ANOVA) to assess the significance of variations across these levels. Results revealed statistically significant differences in both temperature and relative humidity (p < 0.05). At the uppermost level (2.7 m), the highest mean temperature of 22.1°C and a mean relative humidity of 68.2% were recorded, while the lowest level (0.3 m) exhibited the lowest mean temperature of 20.9°C and the highest mean relative humidity of 73.8%. Temperatures at the patient level (1.0 m and 1.7 m) averaged between 21.0 °C and 21.6°C, which is slightly below the optimal comfort range of 22°C to 26°C. These vertical gradients indicate that the existing HVAC systems may not be effectively regulating indoor conditions, potentially impacting patient comfort, the performance of temperature-sensitive dental materials, and the effectiveness of infection control measures due to altered aerosol behaviour. The findings underscore the necessity of optimizing HVAC designs to achieve uniform temperature and humidity distributions within dental treatment rooms. This research provides valuable insights for healthcare professionals and policymakers, emphasizing the importance of tailored environmental management strategies to enhance patient comfort, procedural outcomes, and safety in dental healthcare settings.
  • Publication
    Experimental analysis using thermocouple and infrared thermography of the temperature evolution of lithium-ion polymer cells at different charging rates
    (Springer, 2025)
    A. I. A. Sabandi
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    ;
    M. F. H. Rani
    ;
    N. Maruyama
    ;
    W. K. Wan
    ;
    ; ;
    An experiment was designed to investigate the temperature revolution of lithium-ion polymer (LiPo) cells using two different approaches, thermocouples and infrared thermography. The cells were charged under controlled conditions at rates of 2.0 A, 4.0 A, 6.0 A, 8.0 A, and 10.0 A. The analysis focused on the maximum surface temperature, temperature changes over time, and surface temperature distribution. The findings revealed that higher charging rates result in increased heat generation, causing greater temperature rises, steeper temperature gradients, and higher maximum temperatures. During the charging process, the study also observed endothermic behavior and uneven temperature distribution across the cells. However, upon completing the charging, the surface temperature became evenly distributed without any critical hotspots. Notably, maximum temperatures were observed in the lower regions of the cells for lower charging rates (2.0 A, 4.0 A, and 6.0 A) and in the upper regions for higher rates (8.0 A and 10.0 A). Additionally, infrared thermography provided a clearer and more precise method for measuring surface temperatures compared to thermocouples, as indicated by experimental uncertainty analysis. IR imaging also showed a faster temperature increase at higher charging rates, offering deeper insights into the thermal characteristics of LiPo cells.
  • Publication
    Effect of pineapple leaf (PALF), napier, and hemp fibres as filler on the scratch resistance of epoxy composites
    This article presents the effects of pineapple leaf (PALF), napier, and hemp fibres as filler on the scratch resistance of epoxy composites. In particular, it explores the effect of these natural fillers on the horizontal load, coefficient of friction (COF), penetration depth, fracture toughness, scratch hardness, brittleness index and scratch observation. The mixing method using magnetic stirrer was used to produce the natural fibre-filled epoxy composites with different wt%, namely, 5, 7.5, and 10 wt%. The test was performed using a CSM Revetest Xpress, which consisted of a cone of the half-apex angle of 60° ending with a sphere having a tip radius of 200 μm. The indenter scratch distance and speed were 7 mm and 1.5 mm/min, respectively. The results show that the napier fibre-filled epoxy composites have the highest peak load and COF. It was also noted that the napier fibre-filled epoxy composites have the lowest penetration depth for each wt% of filler. Lastly, the fracture toughness (Kc) for the napier fibre-filled epoxy composites with 10 wt% of filler yielded the highest value of 4.33 MPa.m1/2. It can also be seen that using a scanning electron microscope (SEM), the amount of debris increased with higher of wt% of the natural fibre fillers in the composites. Hence it was demonstrated that the napier fibre-filled epoxy composites have higher scratch resistance compared to the PALF and hemp fibre-filled epoxy composites. Keywords: Surface analysis, Fracture toughness, Scratch resistance, PALF, Napier, Hemp fibres.
      12  19
  • Publication
    Microwave dielectric analysis on adhesive disbond in acrylic glass (Poly (Methyl Methacrylate)) at KU-band
    A microwave dielectric spectroscopy for detecting adhesive disbonds between acrylic glass (aka Poly (methyl methacrylate)) was discussed. The adhesive bond was developed using epoxy resin and acrylate. The level of joint disbond can be quantified using Young Modulus. In this work, the strength of bond is affected by radius of air void within adhesive bond. A high-frequency electromagnetic wave propagated through two joint acrylic glass with acrylate and epoxy adhesive using waveguide adaptor WR90 in conjunction with professional network analyser. This electromagnetic wave is reflected and transmitted at the bond interface due to mismatch impedance at adhesive bond. The output is a dielectric properties that characterizes the bond interface. The increment of Young Modulus leads to increment of dielectric constant and loss factor for epoxy resin and acrylates, respectively.
      7  37