Experimental and numerical simulation of cotton seed oil in the compression ignition engine

In the present work, experimental tests have been carried out to evaluate the performance, emission and combustion characteristics of a diesel engine using cotton seed oil (CSO) and its blends of 20%, 40% and 60%, and standard diesel fuel separately. The common problems posed when using vegetable oil in a compression ignition engine are poor atomisation, carbon deposits, ring sticking, etc. This is because of the high viscosity and low volatility of vegetable oil. When blended with diesel, CSO presented lower viscosity, improved volatility, better combustion and less carbon deposit. It was found that there was a reduction in NOx emission for CSO 100 and its diesel blends along with a marginal increase in hydrocarbon and carbon monoxide emissions. Brake thermal efficiency was slightly lower for CSO 100 and its diesel blends. From the combustion analysis, it was found that CSO–diesel blends performed better than CSO 100. Finally, simulation work is carried out using the computational fluid dynamics FLUENT code to validate the combustion analysis. The experimental results closure to the calculated results. © 2013 The Hong Kong Institution of Engineers.