Theoretical Analysis And Experimental Study Of Diesel Exhaust Gas Purification By NTP Assisted Wood Fiber

With the rapid increase in the amount of diesel vehicles in China,the emissions of PM and NOx has become the main source of air pollution,the traditional method of dealing with diesel exhaust has been unable to meet the requirement of emission regulations because of its inherent limitations.It has become a top topic to purify engine exhaust by Non-thermal plasma?NTP?,NTP assited wood fiber used to purify PM and NOx simultaneously broad application prospects.The suitable discharge devices for purifying engine exhaust was selected through analyzing charateristics of different NTP reactors.The three-phase gas(N_2,NO,O₂)dynamics model was established for NTP purify NOx,the trend of NO,NO₂,O₂,O₃ and O concentration in the model was analyzed.The PFR model of NTP purified NOx was established by CHEMKIN software,the model is solved with the model control equation,analyzing the effects of discharge power,purification time and O₂ concentration on the purification efficiency.Through the comprehensive analysis of simulation,it has been predicted that NTP can simultaneously purify PM and NOx.To verify that NTP can simultaneously purify PM and NOx,it was proposed that NTP combined with wood fiber,a plasma wood fiber purifier model was designed combining NTP with wood fiber,the parameters influencing the purification efficiency was analyzed by simulation test.The simulation results showed that NTP can simultaneously purify PM and NOx,wood fiber can be used as carrier of nanometer cerium oxide,cerium oxide can enhance purification efficiency of purifier as a catalyst,increase the gas temperature can enhance PM and NOx purification efficiency,the input voltage has a great influence on the purifying efficiency of the purifier.The simulation results are in agreement with the prediction.Lastly,the plasma wood fiber purifier was designed for diesel exhaust system,and the engine bench test was be set up,the factors influencing the purification efficiency was compared and analyzed further,experimental results was showed that,plasma wood fiber purifier can effectively purify PM and NOx,in diesel engine exhaust which definitely proves the reliability of plasma wood fiber purifier.When the wood fiber filter filling rate is 0.25,the input voltage is 15kV,the diesel engine for the rated speed,load 40%,diesel exhaust temperature of 210?,the plasma wood fiber purifier purification performance is the best.