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The main challenge in designing the oil pump for gasoline & diesel engines is to optimize the pressure relief passage. Pressure relief passage is critical from design point of view as it maintains the oil pressure in the engine. Optimal levels of oil pressure and flow are very important for satisfactory performance and lubrication of various engine parts. Low oil pressure will lead to seizure of engine and high oil pressure leads to failure of oil filters, gasket sealing, etc. Optimization of pressure relief passage area will also reduce the power consumed by the pump. The Pressure relief system for this study consists of Pressure relief valve, spring, retainer, pressure relief passages. It is difficult to directly measure the flow through the pressure relief passage and is arrived based on the drop in flow at the delivery port. Numerical tool will be handy to predict the flow through the pressure relief passage and this can be used to optimize the flow through the bypass passage.

Gasoline direct injection (GDI) technology is already in use in four wheeler applications owing to the additional benefits in terms of better combustion and fuel economy. The air-assisted in-cylinder injection is the emerging technology for gasoline engines which works with low pressure injection systems unlike gasoline direct injection (GDI) system. GDI systems use high pressure fuel injection, which provides better combustion and reduced fuel consumption. It envisages small droplet size and low penetration rate which will reduce wall wetting and hydrocarbon emissions. This study is concerned with a CFD analysis of an air-assisted injection system to evaluate mixture spray characteristics. For the analysis, the air injector fitted onto a constant volume chamber (CVC) maintained at uniform pressure is considered. The analysis is carried out for various CVC pressures, mixture injection durations and fuel quantities so as to understand the effect on mixture spray characteristics.

The main challenge in today's modern engines is to design the parts, which should withstand higher temperatures. To achieve this, selection of materials and process tolerances are very important factors. The product identified in this study is a conventional oil pump, which is an engine auxiliary component. The function of the oil pump is to supply oil to different parts of the engine to lubricate and reduce the overall engine friction. The different speed and load conditions for which the engine is subjected, pose a challenge to the oil pump, to supply the necessary quantity of oil at the required pressure and temperature. Normally, the oil pump is subjected to a temperature of 120°C at higher speeds. However, the peak oil temperature in modern diesel engines can be as high as 140°C to 150°C for a short period of time. For this study, two engine grade oils were selected. Numerical analysis was performed to predict the oil flow rate for these oil grades.