The Influence Of Surface Roughness In Micro Indentation

The Influence Of Surface Roughness In Micro Indentatio

Topology Optimization Of Spinal Interbody Cage For Reducing Stress Shielding Effect

Intervertebral disc degeneration or damage resulting from acute and chronic spinal injury induces the spine structure instability. Kemerosotan atau kerosakan ceper antara vertebra yang disebabkan daripada kecederaan secara akut atau kronik akan menghasilkan ketidakstabilan struktur spin

In-situ Noise Measurement and Analysis for the Motorcycle Muffler

Noise from the vehicles is one of the noise pollution to the environment. The noises emitted by the vehicles have to obey the requirement of regulation of maximum sound pressure level permitted for respective vehicles. In this study, the aim is to reduce the noise emitted from the motorcycle muffler. The noise emitted from the motorcycle muffler is analyzed and measured using a sound level meter. The average sound pressure level of the motorcycle muffler is determined in certain conditions. The sound pressure level is obtained from original motorcycle muffler, when it is under constant speed (10 km/hr, 20 km/hr, 30 km/hr) and under acceleration (in the scope of 0 km/hr to 30 km/hr). The study is continued by using a modified motorcycle muffler which contains sound absorptive materials. The absorptive materials chosen are glass wool, cotton and Styrofoam and they are taking turn to be placed into the motorcycle muffler to reduce the sound pressure level. Then the experiment is repeated. It is found that Styrofoam does not perform significantly in absorbing sound or noise in this study. Glass wool demonstrates relatively better sound energy absorption compared with cotton. In general, soft and porous materials are considered good performance in sound absorption. Denser materials are better at soundproofing or sound blocking. Therefore, glass wool with relatively higher density among the investigated absorptive materials in this study has the greatest sound absorption performance

A Study on the Tribological Performance of Nanolubricants

In recent years, the tribology field has expanded with the advent of nanolubrication. Nanolubricants are the name given to the dispersion of nanoparticles in a base oil, and has attracted researchers due to its potential application. In addition to being used in the tribology field, nanoparticles are also used for medical, space, and composites purposes. The addition of nanoparticles in base oils is promising because it enhances specific tribological characteristics including wear-resistance and friction, and the most important reason is that the majority of them are environmentally friendly. This paper reviews the tribological effect of various nanoparticles as lubricant additives. Parameters of nanoparticles that affect tribological performance, the technique to enhance stability, and lubrication mechanism that is currently believed to function will be delineated in detail. Moreover, this review facilitates an understanding of the role of various nanoparticles, which helps in developing and designing suitable nanolubricants for various applications

Investigating the Effects of Operational Factors on Wear Properties of Heat-Treated Pultruded Kenaf Fiber-Reinforced Polyester Composites using Taguchi Method

This study investigated the mechanical and wear properties of heat-treated pultruded kenaf fiber-reinforced polyester composites (PKFPCs) using pultrusion technique. A total of three heat treatment temperatures (120, 140, and 170°C) of PKFPC and untreated PKFPC were produced and their performance was compared. Different sliding conditions and different heat treatment temperatures on PKFPC were tested according to the Taguchi orthogonal array design of experiment. The worn surfaces and transfer films produced were examined using scanning electron microscopy. The results showed that PKFPC with a 140°C heat treatment exhibited better wear performance than untreated PKFPC and PKFPC with 120 and 170°C heat treatments. The flexural strength and modulus of PKFPC increased after heat treatment. The counterface roughness and heat treatment temperature are the most significant factors affecting the wear performance of PKFPC. The optimum sliding conditions to achieve lowest wear and friction in the tested operating environment were determined

Effect of Calophyllum Inophyllum biodiesel-diesel blends on combustion, performance, exhaust particulate matter and gaseous emissions in a multi-cylinder diesel engine

In this work, the effects of adding of inedible Calophyllum Inophyllum biodiesel to diesel fuel on performance, gaseous emissions, particulate matter (PM) and combustion characteristics were studied in a medium-duty, high-pressure common-rail turbocharged four-cylinder diesel engine under different speed and torque conditions. The key physicochemical properties of neat biodiesel, biodiesel-diesel blends and diesel were characterized and analysed. The test fuels used were a fossil diesel fuel, B10, B20, B30, and B50 of biodiesel-diesel fuels. The results indicated that all blends of biodiesel fuels have physicochemical properties relatively close to those of petroleum diesel. The experimental results also demonstrated that there are some drawbacks in engine brake power, brake specific fuel consumption (BSFC), and nitrogen oxide (NOx) with the blend of biodiesel in the fuel. Besides, refinement in brake thermal efficiency (BTE) and exhaust emissions were recorded across all engine speeds. Moreover, the emission improvement was characterized by lower carbon monoxide (CO) and reduced in both of the smoke and PM emissions. Also, reduction in the magnitude of peak combustion pressure and heat release rate (HRR) were also found with biodiesel blends. Overall, the results indicated that Calophyllum Inophyllum biodiesel can be used satisfactorily in an unmodified multi-cylinder high-pressure common-rail diesel engine