Experimental Study Of Different Types Of Biodiesel In Diesel Engines And Chemical Dynamics Calculation

The energy crisis and the deterioration of the environment makes it increasingly concerned about alternative of the petroleum fuel, Biodiesel is an alternative, renewable, clean fuel, has become an ideal alternative fuel for petroleum diesel.However, the effects of biodiesel on engine performance vary due to the difference in source. In this paper, performance of three different biodiesels was studied:Waste cooked oil, Jatropha oil, rubber seed oil. Engine power, fuel consumption, gaseous emissions were investigated in a four cylinder Direct Injection CI diesel engine fueled with three biodiesels respectively and compared with the diesel fuel. Results revealed that using different biodiesels resulted in the power of biodiesel is lower than the diesel oil, waste oil power slightly high than rubber seeds and Jatropha oil; diesel fuel has lower specific fuel consumption than biodiesel, Waste cook oil has the lowest fuel consumption among biodiesels; the soot emissions of biodiesel significantly lower than diesel fuel, Jatropha oil has the lowest soot emission among the biodiesels; NOx emissions of biodiesels are significantly higher than thediesel fuel, rubber seed oil NOx emissions higher than Jatropha and waste oil.A combinated chemical kinetic model was builded based on methyl butanoate,methyl crotonate and n-heptane mechanisms,the combinated model contains PAHs and NOx formation reactions and was applied to analysis the effects of unsaturated methyl on the combustion and emission of diesel engine.the results show that the carbon-carbon double bond in the methyl ester will makes the increase in soot precursor and NOx formation.Simulation of combustion emission characteristics of biodiesel also conducted at the same time, the study found diesel fuel emits more soot precursor than biodiesel,and less NOx than biodiesel.