Numerical investigation of the effects of ethanol addition on the performance and emission characteristics of CI diesel engine

The demand for higher output efficiencies, greater specific power output, increased reliability, and ever reduced emissions has been rising. Due to its availability one promising alternative is the use of ethanol in internal combustion engines. In this study, the effects of ethanol addition (5%, 15% and 25% by volume) to diesel fuel on the performance and exhaust emissions of a 6 cylinder four stroke turbocharged direct injection CI Diesel engine were investigated using GT-Power computational simulation tool. The simulations were performed by varying the engine speed between 1000 and 2000 rpm at four different loads of brake mean effective pressure (BMEP) (6.5, 8.5, 10.5 and 12.75bars). The performance and exhaust emissions of the engine when working with the three ethanol-diesels blends were compared with diesel fuel. The results showed that the ethanol-diesel blends reduced carbon monoxide (CO) and nitrogen oxide (NO
_X
) by about 19.3% and 26% respectively, although they caused an increase in unburned hydrocarbon (HC) emissions. It was also found that the brake thermal efficiency (BTE) improved by more than 10% for ethanol diesel blends when compared with the corresponding diesel fuel. Due to its optimum values in terms of emission and performance parameters 15% ethanol-diesel blend was found to be the best choice.