COMBUSTION ANALYSIS AND PERFORMANCE OF LOW HEAT REJECTION DIESEL ENGINE WITH DIFFERENT THERMAL INSULATION COATING

A simulation system has been developed for comprehensive predictions and assessments of the various and interrelated indices of diesel engine performance. A model for the prediction of combustion and heat release has been formulated and developed. The gas-wall heat transfer calculations are based on Annand's heat transfer model for I. C. engine. In the present work, for performance and evaluation at constant speed 850 rpm, 8.5 hp, water cooled single cylinder 4-stroke diesel engine were considered and critically analyzed the performance of low heat rejection diesel engine by using two different thermal insulating material. Thermal insulation materials like PSZ (partial stabilized zirconia) and silicon nitride of 1 mm and 0.5 mm thickness are used on crown of the piston, on cooling side of cylinder liner, on cylinder head and on valves. Heat transfer models have been developed for diesel engine performance with and without thermal insulation coating that is incorporated in the simulated program.

A wall heat transfer model has been formulated and developed and coupled along with the above combustion and gas-wall heat transfer model to predict the effect of varying wall temperature on combustion, heat release, heat transfer and overall performance of a low heat rejection direct injection diesel engine.