Influence of Injector Opening Pressure on Performance Parameters of Di Diesel Engine with Three Levels of Insulation with Diesel Operation

Abstract

Experiments were conducted to evaluate the performance of direct injection (DI) diesel engine with different levels of low heat rejection (LHR) combustion chamber such as i) ceramic coated cylinder head, ii) air gap insulated piston and air gap insulated liner and iii) ceramic coated cylinder head along with air gap insulation with neat diesel operation with varied injector opening pressure. Performance parameters (brake thermal efficiency, exhaust gas temperature, coolant load, volumetric efficiency and sound levels) were determined at various values of brake mean effective pressure (BMEP) of the engine. Engine with ceramic coated cylinder head showed marginal improvement in performance at all loads, engine with air gap insulated piston and air gap insulated liner showed improved performance at 80% of the full load operation while engine with ceramic coated cylinder head, air gap insulated piston and air gap insulated liner showed deteriorated performance at all loads at manufacturer’s recommended injector opening pressure of 190 bar when compared with conventional engine with diesel operation. However, performance improved further with an increase of injector opening pressure with different versions of the combustion chamber.