Analysis For Performance Of Diesel Particulate Filter In ESC Test Cycles

As the development of low-carbon economy, automotive energy-saving and emission reduction has gaining a worldwide attention, the major automobile manufacturers have also taken measures to reduce vehicle emissions. Particulate trap is one of the most effective way to control diesel particulate emissions. Research on DPF has certain value in engineering application. Particulate trap has three basic features:exhaust back pressure, trapping efficiency and regeneration properties. This study focus on these characteristics, analysis the various characteristics of particulate trap and its influencing factors on the road operating conditions.First, A CFD simulation model for currently widely used wall-flow honeycomb ceramic filter was established with ESC test cycle. The effect of the static pressure, velocity and carbon particle volume fraction distributing rules on filter regeneration was conducted. The comparison of the flow conditions and trapping efficiency in several operating conditions of ESC test cycle was analyzed. Simulation results show that a better trapping efficiency is taken place in high-speed operating conditions, and at the same time there are higher flow speed and larger exhaust back-pressure.Then, with ESC operating conditions, considered the continuous passive regeneration of particulate trap, analyzed its effects on the exhaust back pressure and trapping effects, and with the changes in working conditions, analyzed the effects of its regeneration. The results show that:Particulate Trap in various operating conditions have a good trapping efficiency and the regeneration effect. continuous regeneration can also reduce the exhaust back pressure and improve trapping efficiency; in various operating conditions, seem that the low-speed, high loading operating conditions would achieve a better regeneration.Finally, with different conditions, analyze the influence of air flow rate, temperature and mass concentration of NO2 and C on continuous regeneration. The results show that: low-speed, high temperature, and a higher NO2 and lower C concentrations would have more conducive to regenerate reaction. And thus analysis the continuous regeneration of different operating conditions with intensive study.