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A cycle simulation program has been formulated and developed for a conventional and a Low Heat Rejection (LHR) direct injection diesel engines operated with biodiesel. Model for the prediction of heat transfer, heat release, cylinder pressure data, overall performance and emission levels were synthesized and analyzed. The combustion chamber (includes crown of the piston, cylinder head, valves and liner) has been coated with partially stabilized zirconia (PSZ) of 0.5 mm thickness. Methyl esters (called biodiesel) have been derived from non-edible vegetable oil such as Jatropha oil. In this work, the combustion, rate of heat release, cumulative heat release, rate of heat transfer with and without thermal barrier coating have been considered and analyzed.

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.

Energy conservation and emissions have become of increasing concern over the past few decades. As automobiles are one of the major sources of energy consumption and urban emissions, engineers concerned are under significant pressure to improve their energy efficiency and reduce exhaust emission levels. While tremendous effort has been devoted in improving performance and reducing emissions of current engines, new technologies are also getting attention. One example is the Low Heat Rejection Engine (LHRE). A technological thrust is currently in progress to develop insulated, low heat rejection engines which exhibit higher thermal efficiency and improved exhaust emissions. The low heat rejection engine concept is not new. For the past two decades many have conducted experiments on low heat rejection engines. Although promising, the results of the experimental investigations have been somewhat mixed.

Heat transfer analysis of the braking system can guide us to evolve an efficient method of cooling of braking system components. In the braking systems, the disc brake can be effectively cooled because, its simpler construction. Even though the heat transfer is relatively easier, in the varied dynamic operating condition of the vehicle, it is relatively complicated to quantify the amount of heat transfer. Under the circumstance of varied heat transfer it is advisable and justifiable to go for a virtual heat transfer analysis through an appropriate computer code based on the standard heat transfer concepts and relations. This paper deals with the convective and radiative heat transfers from the disc brake components based on the fundamental relations for the above heat transfer mechanisms. In this study, the virtual heat transfer analysis was carried out for a typical disc brake system of a four-wheeled passenger comfort vehicle.

A comprehensive analysis of combustion, heat release, heat transfer and performance of a low heat rejection diesel engine was carried out for its potential development over the conventional diesel engine. A model for the prediction of combustion and heat release has been formulated and developed, based on the two zone combustion modelling concept of WHITEHOUSE.N.D/WAY.R.J., and BALUWAMY.N. The combustion model takes into consideration on a zonal basis, the details of spray formation under non-swirl and swirling conditions, spray wall interaction, heat transfer, preparation and reaction rates. The penetration, deflection and growth of the spray are calculated based on the momentum added due to entrainment under swirl and non-swirl conditions. The combustion parameters were calculated based on the first law of thermodynamics using energy and enthalpy coefficients. The gas-wall heat transfer calculations are based on ANNAND.W.J.D, ANNAND.

This paper presents a general overview about the previous research efforts into Low Heat Rejection Engine (LHRE) concept. The purpose of this paper is to explain the effect of insulation on engine performance, heat transfer characteristics, combustion and emission characteristics. Many researchers have carried out a large number of studies on LHRE concept. Some of them are experimental work and many are theoretical studies. In the case of LHR engines almost all theoretical studies predict improved performance but many experimental studies show different picture. This paper analyzes the reason for this deviation. The operating conditions, under which the experimental and simulation studies are carried out, have been clearly discussed. The factors, which affect thermal efficiency, combustion, and exhaust emissions in LHR engine, are deduced and their influences discussed. Effect of fuel injection characteristics on LHR engine performance is also reviewed.