Now showing 1 - 10 of 13
  • Publication
    Influence of different materials on the mechanical aspects in the design of cyclone gasifier
    Cyclone gasifier is used as the energy conversion system for the biomass. The design and material selection for the cyclone gasifier is important, which affect the strength of the gasifier during the operation. This research aims to investigate the effect of the various materials to the mechanical aspects (i.e., stress, strain and displacement) of the cyclone gasifier. The mechanical aspects analysis is carried out by using the finite element (FE) based software. The stress, strain and displacement of the cyclone gasifier’s structure was analyzed for various stainless steel materials (i.e., ferritic (FSS), AISI 316, 1023 CSS, 201 ASS and AISI 4130). The finite element analysis revealed the use of 201 ASS experienced highest stress (221 MPa). Lowest strain and displacement were found on 201 ASS and 1023 CSS, respectively. These research findings are expected to be used as the reference for the engineer in the material selection process for the design and fabrication of cyclone gasifier.
  • Publication
    Experimental and computational evaluations of the mechanical stresses of banana trunk fibre-reinforced epoxy resin composite in coffee table application
    The banana plant including the trunk is normally disposed after it has produced fruits once in its lifetime and becoming unproductive. Herbicide injection and burning using kerosene are the examples of current disposing method. Those methods are unfavourable owing to bad effects to the environment. Therefore, the unproductive banana trunk through its fibre properties, has a high potential to be used as composite in saving the environment. Three tensile test specimens were prepared with two of them have different length of banana fibres – shorter and longer than 0.5 mm, whilst another specimen has no fibres. The elastic modulus, Poisson’s ratio, and vertical load of 2 GPa, 0.3, and 981 N, respectively, were applied towards numerical models. The results exhibited that the composite with short banana fibre length promoted encouraging maximum and break stress values. Besides, the properties of the composite are well appropriate to be applied in furniture making as satisfactory stress value recorded in the computational analysis.
  • Publication
    Numerical Simulation of Biodiesel Synthesis in T- Channel Microreactor
    Biodiesel promising as an alternative to the diesel. The transesterification reaction process involved the reaction of triglyceride with alcohol in the presence of catalyst. In the research, the Computational Fluid Dynamic (CFD) method was used to simulate the transesterification reaction process. The inlet pressure range from 0.0001 Pa to 0.01 Pa, temperature of 25°C, 50°C, 75°C and the molar ratio at 6:1, 9:1 were used to investigate their effect of toward the biodiesel conversion. Finding shows that high conversion of biodiesel occurred at low inlet pressure of 0.001 Pa with temperature of 50°C and the ethanol to oil molar ratio at 9:1.
      2  32
  • Publication
    Effect of heat sink design on the thermal characteristic in computational fluid dynamics analysis
    The thermal management in the electronic device or system using the heat sink is important to ensure the device or system operating under the allowable temperature. The present study aims to investigate the thermal characteristic (i.e., temperature distribution) of the various heat sink designs via computational fluid dynamics (CFD) analysis. The electronic cooling process of the heat sink is carried out via CFD software. The temperature distribution of the various heat sink designs (i.e., plate fin, circular pin fin and rectangular fin) was analyzed and compared. The CFD analysis revealed the plate fin heat sink has lowest temperature distribution on the fin region. High temperature distribution was observed on the pin fin heat sink. The non-uniform temperature distribution was attributed by the direction of inlet airflow, whereas the low temperature was found in the region that close to the inlet airflow. Thus, the research findings indicated the design of heat sink significantly affects the temperature distribution during the electronic cooling process.
      3  28
  • Publication
    Simulation-based optimization of plastic injection molding parameter for automotive car wheel fabrication using Response Surface Methodology (RSM)
    In the era of revolution industry 4.0, most companies can expect metal-to-plastic conversion to result in cost savings. The objectives of this study are to find the most appropriate material composition and the injection molding process parameter to produce a plastic car wheel as a substitute for metal and aluminum alloy. The Polyetherimide (PEI) with different compositions are simulated using MoldFlow software and optimized the quality of injection molding process parameter by using Central Composite Design (CCD) in Response Surface Methodology (RSM) as to get an optimal response and meets the car wheel requirement specification. The crucial factors are melting temperature, injection time and cooling time. The quadratic model fits the model response. As the results, the optimum values suggested by the software were melt temperature of 370.27°C, 1.8s of injection time and 2599.89s of cooling time for 0% of filler (pure PEI). With small differences error value between solution and simulation, 0.1% of shrinkage and 0.9% for warpage, the results were acceptable.
      10  2
  • Publication
    Computational Fluid Dynamics (CFD) Simulation on Mixing in T-Shaped Micromixer
    Computational Fluid Dynamics (CFD) simulation used to analyse the fluid mixing in micromixer. There are two cases of miscible liquids that involved within T-shaped micromixer which are ethanol-water and glycerol-water. The T-shaped micromixer consist of micro channel with two inlets channels and one outlet channel was constructed by using AutoCAD software. The effect of inlet velocity and width size toward mixing intensity were investigated. The mixing intensity values determine either good or bad mixing quality could be achieved. In this simulation, at low inlet velocity indicates good mixing quality as the mixing intensity value approaching to one. Whereas the effect of width size on mixing intensity are almost similar throughout simulated width sizes. Mixing intensity for the two cases of diffusion coefficient showed similar trend for different inlet velocity and width size of mixing channel.
      7  26
  • Publication
    Simulation Based Optimization of Thin Wall Injection Molding Parameter Using Response Surface Methodology
    Improper mold design or processing parameter setting could make a bad impact on the appearance of molded part. It becomes more challenging if the ratio of the part size compared with its wall thickness is greater. Process parameters such as mold and melt temperature, injection temperature including the cavity layout directly affect product quality and cost. It is a complex and difficult task to improve these multi parameters. The objective of this research is to determine optimum settings for processing parameters for a thin walled product by using Response Surface Methodology. Melting temperature, mold temperature, injection pressure and cavity layout are selected as processing parameters and Polyurethane material is selected for this research. Volumetric shrinkage and warpage are selected as the main quality criteria to be controlled respected with the product design specifications. As the result, optimum process parameter settings were mold temperature of 29.89°C, melting temperature of 220°C, and 181.30MPa injection pressure with 'H' branching cavity layout. With small differences error value between solution and simulation, 0.31% for volumetric shrinkage and 0.126% for warpage, the result was acceptable.
      5  30
  • Publication
    Biomechanical assessment of different surgical approaches of zygomatic implant placement on prosthesis stress
    The treatment of severely atrophic posterior maxillae without bone augmentation by using zygomatic implants has received a major attention in prosthodontics due to great implant survival rates. However, mechanical implant system failures were still reported irrespective of surgical techniques used for zygomatic implant placement. Two main prominent approaches, the intrasinus and extramaxillary possess their own advantages and drawbacks with no particular indication found, to date, to highlight the best technique in relation to prosthesis stress. Thus, this study emphasised on the computational evaluation of both approaches with regards to the prosthesis responses. Two sets of finite element models comprising bones, soft tissue, implants, abutments, and prosthesis were prepared accordingly. The models were then assigned with the material properties, contact modelling, and loadings as closely as possible with the real conditions. The results showed that the extramaxillary technique reported a more promising maximum stress value and distribution within the prosthesis than the intrasinus. Moreover, the prostheses in both approaches seemed to have a low tendency to failure as the stress levels were significantly less than the stress limit of the material.
      4  38
  • Publication
    Effect of zinc addition on the performance of aluminium alloy sacrificial anode for marine application
    In this work, the effect of zinc addition on the performance of aluminum-based sacrificial anode in seawater was investigated. The parameters used in assessing the performance of the cast anodes are anodic efficiency, protection efficiency and polarized potential. The content of zinc in the anodes was varied after die casting. The alloys produced were tested as sacrificial anode for the protection of mild steel for marine application at room temperature. Factors such as reactivity of zinc particles in the seawater, corrosion activity during the period of experiment, pH of seawater and the electronegativity potential of zinc were collected for analysis. Overall findings shows addition of zinc increases rate of corrosion to the sacrificial anode and the protection offered by the sacrificial anodes measured and collected in PIT shows the seawater react to sacrificial anode and no porosity reaction between the anodes. The microstructure showed the intermetallic structures of β-phase which breakdown the alumina passive film, thus enhancing the anode efficiency.
      46  2
  • Publication
    Effect of twist blade distributor on velocity distribution in a swirling fluidized bed
    Swirling Fluidized Bed (SFB) is one of the liquid-solid interaction in fluidization improved from conventional systems. This system is usually viewable in the power generation, chemical industry, material production and drying processes. Inside the SFB, there is annular blade distributor which will cause the air to pass through and create a swirl motion on the bed. The energy consumption of a fluidized bed system depends on the distributor’s design. The current study has purpose a new design that applies to existing designs of blade inclination angle. The simulation study was conducted using Computational Fluid Dynamics (CFD) to obtain the result of velocity distribution and pressure drops on various blade distributor designs. This study uses two (2) twist angle (80° and 100°) via number of blade distributor (40, 50 and 60). In this study, tangential velocity is the main velocity component by reason of the velocity represents the rotating air velocity in fluidization system. Overall, the design of the 100° twist angle and 40 blades distributor are the best distributors of blades compared to others.
      4  26