Numerical Analysis Of Combustion Process In Diesel Engine With Biodiesel Mixture

Biodiesel is a typical "green energy", perfect for substituting petroleum diesel. It can bemade from many plant oils,animal grease and waste edible oils. The characteristicsof biodiesel is low content of sulfur and aroma hydrocarbon, high content ofoxygen, high cetane value and flash point, less hazardous exhaust gas. It hasgreat meanings to the environment protection and the development of our nationaleconomy with large scale application.This paper has investigated the combustion characteristics of B20 using thenumerical simulation, and then discussed the performance and the characteristicsof exhaust.At the beginning, it introduced the general situation of biodiesel, and then dissertated thecharacter of biodiesel and discussed the influence of character to the performance andexhaust.Then, the program of KIVA is applied to simulate the combustion process of biodiesel,and then compared the simulation result to the diesel oil's.The main conclusion of the paper is that the character of blend-oil is similar to diesel,and can be used in diesel engine. The glutinosity of biodiesel is bigger than diesel, and makethe atomization not well. Biodiesel contains about 10% oxygen, and oxygen of blend-oilparticipate in the process of combustion, and reform the combustion, and reduce the exhaustof CO,CO₂. The exhaust of NO is increased, and it is several reasons. Because it is containoxygen and can produce high temperature environment make the NO high. Another reason isthe character itself. But the influence is little, and can reduce the exhaust of NO through somemethods. Our country consume a lot of oil every year. If the diesel can be appended somebiodiesel, about 5%～10%, then can save a lot of oil, and also can develop the biodieselindustry. The analysis shows that this way is feasible.