Performance of rapeseed methyl ester in diesel engine

Vegetable oils have an ignition quality equivalent to diesel fuel and their combustion characteristics are much similar, but their viscosities are too high making them unsuitable for modern fuel pumps. The vegetable oil esterification represents one approach to overcome the problems associated with the high viscosity of neat vegetable oil when used as substitute for diesel fuel. The paper presents the results of a research work carried out to evaluate the performance of rapeseed methyl ester (RME) on unmodified diesel engine. The paper compares the effect of using RME in a diesel engine with baseline test on diesel fuel. The test results on rapeseed methyl ester showed high friction power with a net reduction in hydrocarbon emissions. The carbon deposits on the injector were similar to those observed when running on diesel fuel. Fuel dilution of the lubricating oil was noted indicating an incomplete combustion due to the still low volatility of plant fuel.