Experimental Investigations on LHR Single Cylinder Air Cooled Diesel Engine using Simarouba Biodiesel and its Blends as Alternate to Diesel Fuel

Abstract

Experiments are conducted to study the performance, exhaust emissions and combustion characteristics of a conventional and LHR diesel engine running with simarouba biodiesel (100%) and its blends (10, 20 and 30% by volume) with diesel as an alternate fuel to neat diesel. The conventional engine is modified as LHR engine by coating 300 μm of PSZ on the piston crown which acts as thermal barrier and reduces heat loss to cooling medium and increases in-cylinder temperature by 50 to 100°C. Conventional and LHR engine are tested with neat diesel, biodiesel and biodiesel blends at an injection pressure of 200 bar and injection timing of 23° btdc. The load is applied in steps of 25% from no load to full load and results obtained are analyzed. LHR engine performed better compared to conventional engine; improved performance, significant reductions in exhaust emissions (except NOX) and improved combustion characteristics for all the blends tested. The percentage increase in brake thermal efficiency of neat diesel, SBD10, SBD20, SBD30 and SBD100 in LHR engine is 1.98, 5.61, 6.0, 3.98 and 2.98, respectively compared to conventional engine at 75% of full load. Amongst the blends tested, SBD20 proved to be better in both the engines. In LHR engine with SBD20 the percentage increase in brake thermal efficiency, pressure rise and heat release rates are 11.28, 6.35 and 14.0, respectively compared to diesel in conventional engine. Percentage decrease in carbon monoxide, hydrocarbon and smoke opacity is 50.0, 46.43 and 40.0, respectively as compared to diesel in conventional engine.