Study On The Manufacturing Process And The Filtering Mechanism Of Carbonized Micron-Wood Fiber Particulate Filter

With advances of inner clean technology of diesel engine, particulate matter in diesel exhaust emissions become smaller and smaller.Numerous studies show that small particles emitted by diesel vehicles are very large harmful to human health, so more and more countries focus on motor vehicle emissions of small particles. This paper summarizes the current diesel exhaust emission regulations and the current inside the outside exhaust treatment technology at home and abroad and compares the structure and performance of the current Diesel Particulate Filter(DPF)。On the basis of the research on micron wood fiber at home and abroad, this paper proposes the application of micron wood fiber as raw material of diesel particulate filter.Combined with the main parameters of the DPF performance, the structural characteristics of micro wood fiber and the filtration theory of fiber filter,the paper derives the filtration mechanism of the inertial effect,blocking effect and diffusion effect of a single micron wood fiber and merges the three major filtering mechanisms.Using a combination of theoretical and experimental methods the paper calculates the permeability and inertia coefficient of the DPF and obtains the relationship of filtration rate, the DPF length and filter pressure drop.According to general principles of finite element software,in this paper it establishs a three-dimensional model and meshs the model of the Carbonized micron-wood fiber particulate filter. According to the characteristics of hydrodynamic software the paper uses the computational model and sets the energy equation and the turbulence equations.Finally, using the multiphase flow model it obtains the parameters of pressure, velocity, particle trajectory within the flow field of the particulate filter.Lastly the manufacture craft of the micron wood fiber and the Diesel Particulate Filter are researched. Initially the optimal process parameters of hot pressing and carbonization are selected.According to a simple comparison test, it can be seen that soot emissions have been significantly improved in the same working conditions after equipmented the micron-wood fiber particulate filter.Built performance test platform of the particulate filter and developed a real-time monitoring system to the performance test platform. The experimental results confirmed the accuracy of calculation.