| Among the several approaches to reduce the pollutant emissions, dielectric barrier discharge plasma based on gas discharge can reduce efficiently the emission of diesel exhaust gas and cannot cause secondary pollution, and shows promise. However, most researches about non-thermal plasma are being done using simulated gas mixtures in laboratory, and many effects are little considered. Based on the fact of reaction, computer simulating can make hypothesis theoretically and design and optimize experiments. Currently, computer simulating is widely used in non-thermal plasma researches.In this thesis, plasma treatment mechanism of NO in exhaust has been researched theoretically; meanwhile, kinetic characteristics for dielectric barrier discharge have been discussed. Considering diffusion and non-diffusion of particles from micro and macro view respectively, kinetic models were constructed. The effects of main micro-discharge parameters to NO removal rate and the relation of removal rate and removal efficiency were analyzed by computer simulating. Conclusion was as following:Removal domain was increased and removal rate was increased in the same position with parameters increased; to certain parameters, removal rate was decreased with removal domain of micro-discharge increased because of particles'diffusion; removal rate was increased with time extended; the relation between removal rate and removal efficiency was non-linear, In the same treatment time, removal rate and removal efficiency were higher when the value of parameters were smaller. Removal efficiency increased with removal rate increasing at the beginning, while removal efficiency was identical even decreased later. High concentration of O2 and NO caused the decreasing of removal rate.Studies in this thesis are helpful to find the optimizing relation between removal rate and removal efficiency, and can be preliminary theoretical foundation for realizing removal device application in diesel engine.
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