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In this paper an effort has been made to simulate the combustion and performance of a turbocharged diesel engine fuelled with oxygenate blended diesel. In this simulation a comprehensive analysis of combustion, heat release, heat transfer and performance of a turbocharged diesel engine was carried out with Diethylene glycol dimethyl ether (Diglyme) blended diesel. The CI engine cycle was simulated for both neat diesel and oxygenate blended diesel fuel operations with a closer duration of each degree crank angle. Heat release was calculated using WIEBE's heat release model under the consideration of two-zone combustion. The thermodynamic property at each degree crank angle was calculated based on the first law of thermodynamics. The fluid motion is considered with swirl inside the engine cylinder. The gas-wall heat transfer calculations are based on ANNAND's heat transfer model for IC engines.

Blending an oxygenate with diesel fuel modifies chemical and physical properties that can alter the engine operating parameters, combustion and emission levels. In this paper an effort has been made to simulate the performance of a direct injection diesel engine fuelled with oxygenate blended diesel. In this simulation the CI engine cycle was simulated for both diesel and oxygenate blended diesel fuel with a closer duration of each crank angle degree. The thermodynamic property at each crank angle is calculated based on the first law of thermodynamics. The fluid motion inside the engine cylinder is considered for simulation. Heat release was calculated using WIEBE's heat release model considering two-zone combustion. The gas-wall convection heat transfer is calculated using ANNAND's heat transfer model considering combustion chamber temperature swings. In the gas exchange model, gas flow rates during intake and exhaust systems were calculated.

Automobile OEM's around the world are looking to improve their overall vehicle and engine efficiency in terms of fuel economy and power output. Efficiency improvement is possible by cutting down the engine parasitic loads. Lubrication oil pump is one such source for parasitic loss of multijet diesel engine. One best way of reducing the same is by optimizing the power consumed by the oil pump without appreciably affecting the flow requirements of the engine. This paper describes an effective approach to bring down the power consumption of a fixed displacement oil pump by keying out various factors contributing for the same. Detailed here are the methods used for identifying those factors, modifications carried out in the design, and testing methods employed for the estimation, together with the results achieved. The test results show that it is possible to improve the power consumption of oil pump by 18% as a result of this study.

In modern research, computer simulation has become a powerful tool for IC engine performance prediction as it saves time and is also economical. A proposed theory or an innovation can be analyzed quickly using a computer and the setting up cost for an experimental work can be postponed until optimization is achieved. For the purpose of evaluating performance of direct injection diesel engine operated with neat oxygenated fuel, the literature data were found confined to experimental investigations and insufficient to serve the purpose because of the large number of oxygenated fuels available for testing. Any improvement predicted in the combustion of the engine fuel will enhance the performance and reduce the emission simultaneously. Therefore oxygenated fuel combustion predictive capability is a acquit necessity at this point of time to screen the oxygenated fuels for better performance.

Automobile OEM's around the world are looking to improve their overall vehicle and engine efficiency in terms of fuel economy and power output. Efficiency improvement is possible by cutting down the engine parasitic loads. One such parasitic load is the oil pump, which lubricates the engine parts. Oil pump is the heart of an engine lubrication system, and its important functions are cooling and lubricating the engine moving parts by delivering adequate oil flow based on the engine demand. Insufficient or no oil delivery from the oil pump leads to the seizure of the engine. The internal vane type oil pump is one kind of positive displacement type pump, where oil gets transferred from the oil sump into the inlet volume. The negative pressure is created inside the pumping chamber due to increase in area. As the vane rotates eccentrically with respect to the stator, it delivers the oil at a higher pressure from inlet to outlet and supplies to engine gallery through the discharge port.

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.

A proposed modification or an innovation can be analyzed quickly using a computer simulation and cost overrun in setting up an experimental work can be minimized by the optimization of experimental parameters beforehand. Literature data for performance prediction of direct injection diesel engine operated either with diesel fuels having property variation or with oxygenated diesel blends were found mostly confined to experimental investigations only. In modern research, computer simulation has become a powerful tool for diesel engine performance prediction as it saves time and is also economical in the analysis of modifications. In a finely tuned and warm engine, the thermodynamic models are capable of reproducing cylinder pressure and over all engine performance with acceptable accuracy over a wide range of operating conditions.

The main challenge in today's modern diesel engines is to design the parts, which should withstand higher temperatures. To achieve this, selection of materials and tolerances are very important. The product identified for this study is an oil pump, which is an engine auxiliary component. The function of 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 condition for which the engine is subjected pose a challenge to the oil pump, to supply necessary quantity of oil at required pressures. 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. When the existing pump was tested at full speed and suddenly decelerated to idle speed, it was observed that the minimum oil pressure was not maintained for engine lubrication.

Oil pump is one of the important engine parasitic loads which takes up engine power through crankshaft to deliver oil flow rate according to engine demand to maintain required oil pressure. The proper functioning of oil pump along with optimum design parameters over various operating conditions is considered for required engine oil pressure. Pressure relief passage is also critical from design point of view as it maintains the required oil pressure in the engine. Optimal levels of oil pressure and flow are very important for satisfied 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 along with other internal systems will also reduce the power consumed by the pump.

Fuel Economy & CO2 Reduction in IC Engines is the key driving factor for the Product performance & Customer satisfaction all around the world. The Stringent CO2 Limits calls for Engine Friction Reduction, Engine Downsizing & other Alternative measures. The challenges were to measure the component level Friction Contribution on the Engine & to select the critical contribution parameter & to optimize the same. Oil pump is one such important engine parasitic load which takes up engine power through crankshaft to deliver oil flow rate according to engine demand. The proper functioning of the Oil pump is considered with required engine Oil pressure along with optimum power consumption over various operating speed and temperature. Hence the various Oil pump critical design metrics are reviewed for two cylinder Multi-jet diesel engine to have optimal power consumption and without reduction the Oil pressure at the engine oil gallery.

Oil pump is one of the important engine parasitic loads which takes up engine power through crankshaft to deliver oil flow rate according to engine demand to maintain required oil pressure. The proper functioning of oil pump along with optimum design parameters over various operating conditions is considered for required engine oil pressure. Pressure relief passage is also critical from design point of view as it maintains the required oil pressure in the engine. Optimal levels of oil pressure and flow are very important for satisfied 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 along with other internal systems will also reduce the power consumed by the pump.

The increasing demand for higher specific power, fuel economy, Operating Costs as well as meeting global emission norms have become the driving factors of today’s product development in the automotive market. Substitution of high-density materials and more precise adjustment of material parameters help in significant weight decrease, but it is accompanied by undesirable cost increase and manufacturing complexity. This becomes a challenge for every automotive engineer to balance the above parameters to make a highly competitive design. This work is a part of the Design and Development of 2.2 L, 4 Cylinder TCIC Diesel Engine for a whole new vehicle platform, concentrated on automotive passenger car operation. This paper explains the selection of a suitable cylinder head gasket technology for a lightweight engine that acts as a sealing interface between the cylinder block and cylinder head.

Lubrication systems play a major role not only in the durability of modern IC engines but also in performance and emissions. The design of the lubrication system influences the brake thermal efficiency of the engine. Also, efficient lubrication reduces the engine's CO2 emissions significantly. Thus, it is critical for an IC engine to have a well-designed lubrication system that performs efficiently at all engine operating conditions. The conventional lubrication system has a fixed-displacement oil pump that can cater to a particular speed range. However, a fully variable displacement oil pump can cater to a wide range of speeds, thereby enhancing the engine fuel efficiency as the oil flow rates can be controlled precisely based on the engine speed and load conditions. This paper primarily discusses the optimization of a lubrication system with a Variable Displacement Oil Pump (VDOP) and a map-controlled Piston Cooling Jet (PCJ) for a passenger car diesel engine.