Studies On Reverse Pulse Air Regeneration For Diesel Particulate Filters

It is well known that Diesel particulate filter (DPF) is an effective way to control particulates emission. But it has not still been widely applied because of the problems that the filter is easy to heat damaged during regeneration and it requires ultra-low sulfur fuel when operating. Considering above problems, reverse pulse air regeneration for DPF is studied in this paper to meet high-sulfur fuel.Wall-flow ceramic filter is widely used in the field of engine's emission control. Based on the analysis of filtration mechanism and filtration process of wall-flow filter, pressure drop model and soot deposit model are developed by the application of porous media flow and two-phase flow theory. The resistance distribution and the deposited particulates distribution in wall-flow filters are investigated, and they are helpful to filter's reliable regeneration.The definition of filter's regeneration efficiency and its calculating method are illustrated based on the mechanism of filter's reverse pulse air regeneration. Using method of bench experiments and simulation, reverse pulse air regeneration system with wall-flow filter is designed and optimized. Sweeping regeneration scheme with helically blowing is presented and regenerating control parameters, such as air pressure, air injection time and sweeping time, are matched. The configuration of removed particulates collection and disposal is optimized to minimize energy consumption. At last the technology developed in this paper is applied successfully to a vehicle.Through the studies of engine's particulates emission rules on different emission characteristics and different operations, regeneration control strategy suitable to reverse pulse air regeneration of DPF is determined, then automatic control system which can be used in vehicles is developed.Bench test and road test results show that the system's remove efficiency for particulates is above 90%, the reduction of both vehicle's power and fuel economy are below 5%, the performance of reducing noise is better than the vehicle's original muffler and the start of the vehicle is not influenced because of using storage battery to combust removed particulates.