Mesoscopic Numerical Simulation And Application Design Of Three-way Catalytic Converter

With the rapid development of China's economy,automobile has become an important part of people's life,and the resulting exhaust pollution has gradually become a serious problem.At present,the three way catalyst(TWC)is one of the important devices to control emissions and solve exhaust pollution.It has obvious effect and is widely used.The service life and conversion efficiency of the three-way catalytic converter are largely limited by the flow field inside the catalytic converter,mainly including the flow uniformity and flow resistance characteristics.Therefore,it is of great practical significance to study the flow performance of the three-way catalytic converter for vehicles.Based on the characteristics of the flow field including porous media and temperature field in the three-way catalytic converter,a device combining porous media flow field and thermoelectric module is built in this paper.The velocity field and temperature field are simulated by lattice Boltzmann method.Lattice Boltzmann method(LBM)is a new tool developed in recent decades to solve complex flow modeling and simulation.Different from the traditional methods of fluid calculation,lattice Boltzmann method is based on the molecular dynamics theory,which is continuous at the micro level and discrete at the macro level,so it is called mesoscopic simulation method.Compared with the traditional CFD method,lattice Boltzmann method has the advantages of easycoding,simple boundary processing and parallel operation.In this paper,lattice Boltzmann method is used to simulate and analyze the internal flow field of three-way catalytic converter.Through the establishment of different physical models and Simulation of different physical parameters(such as inlet speed,inlet temperature,expansion angle,contraction angle,porosity of porous media filter element and filter gap,etc.)on the flow field of three-way catalytic converter,the optimal design of three-way catalytic converter flow field is obtained.By simulating the temperature distribution of thermoelectric module under different physical parameters,the reasons that affect the efficiency of power generation are obtained,which proves the reliability of the design.The research in this paper provides a theoretical basis for the design and development of three-way catalytic converter and thermoelectric power generation device.