Numerical simulation of non-catalytic NO_x reduction for diesel engine

The nitrogen oxides(NO_x) in the exhaust of diesel engine has become the main source of urban air pollution,and the numerical simulation of the selective non-catalytic reduction(NO_x)system for diesel engine with 40%methylamine(CH_3NH_2) aqueous solution as a reducing agent was proposed.To solve the diesel exhaust gas purification has an important guiding significance.This paper uses methylamine selective non-catalytic reduction technology and carries out the engine bench test to establish 13 kinds of physical parameters database of methylamine.CHEMKIN established the reduction process of gas phase chemical reaction mechanism of file into software FireV2011 and the numerical simulation of the reduction process of SNCR system is carried out.The results show that the SNCR test system of the diesel engine increases with the engine exhaust temperature and the NO reduction rate increases rapidly,and the highest NO conversion rate can reach 70%.The results of the numerical analysis of the conversion rate is 65%,indicating the feasibility of the simulation method.With the increase of the reaction time,the NO concentration decreases gradually,and in a reaction cycle starting from the reduction agent injection,NO is fully reduced.