Optimization of combustion performance and emission of Jatropha biodiesel in a turbocharged LHR diesel engine

Abstract

Bio-diesel derived from the vegetable oils are identified as an excellent alternate fuel for petroleum based diesel fuel used in diesel engines. However, the performance characteristics of biodiesel fuel (BDF) are lower than diesel fuel (DF) due to higher variation of fuel properties such as kinematic viscosity and heat content of biodiesel fuel, but it offers an excellent opportunity as an alternate energy source with energy economy to the transport sector. The test engine was modified by converting the existing turbocharged (TC) direct injection (DI) diesel engine to LHR turbocharged DI diesel engine by ceramic coating of combustion chamber (includes piston crown, cylinder head, valves and cylinder liner) with partially stabilized zirconia (PSZ) of 0.5 mm and 1 mm thickness. The experiments were conducted in both conventional turbocharged diesel engine and LHR turbocharged diesel engine to study the combustion, performance and emissions of diesel and Jatropha biodiesel with various volume ratios. A comprehensive simulation code was developed to study the combustion, performance and emissions of diesel and Jatropha biodiesel for conventional turbocharged diesel engine and LHR turbocharged diesel engine. The mass, energy and state equations are applied to yield local temperatures and cylinder pressure histories. Whitehouse Way s methods of calculations are used for the prediction of combustion parameters and heat release analysis. Annand s combined heat transfer model (convective heat transfer and radiative heat transfer) was used to calculate the total heat transfer. The nitric oxide (NO) concentration was estimated through the equilibrium reaction kinetics. The experimental results of conventional turbocharged diesel engine and LHR turbocharged diesel engine were validated and compared with theoretical findings obtained from the relevant computer program. The combustion performance and emission results are found to be satisfactory on comparison of the simulated and experimental results. newline newline newline