Gong Jin-ke

Study on the Exhaust Back-pressure Threshold-value MAP for the Diesel Particulate Filter Regeneration

The back-pressure gradually rises with the increasing particulate sediment during the diesel particulate filter (DPF) working. it will be harmful to the fuel economy of diesel engine. In order to keep the good fuel economy, when the back-pressure exceeds the set threshold-value, the sediment particulate must be cleaned in DPF namely regeneration, therefore, the exhaust back-pressure threshold-value for every working condition is pivotal to the DPF regeneration time. Taking the burner-type DPF as an example, through the real-time measure data of the diesel engine rotate speed, load, corresponding fuel consumption and DPF exhaust back-pressure, with the data processing method and the diesel engine fuel consumption ratio mode based on the multiple regression theory, taking advantage of MATLAB mighty function in mathematic operation and figure disposal, the fuel consumption characteristic map of the diesel engine equipped with DPF is plotted. Further, with the above corresponding test data, the DPF regeneration MAP of exhaust back-pressure threshold-value is obtained.

Simulation and grey relational analysis of continuous regeneration “balance point” of diesel particulate filters

Based on the bench test, a model describing the performance of the CR-DPF has been derived. Proposing the pressure drop of regeneration “balance point” as an evaluation criterion of the regeneration performance of the diesel particulate filter during the steady-state conditions, on the basis of the numerical simulation, the grey relational theory was applied to calculate the relational degree between the “balance point” and the parameters of emission. During low temperature area(280°C;∼450°C), it was showed that the gas velocity, the exhaust temperature, the mass fraction of NO<inf>2</inf> and m(NO<inf>2</inf>)/m(soot) are the main factors, and the mass fraction of O<inf>2</inf> is relatively minor.

Study on Structure Optimization of Diesel Particulate Filter Based on Flow Field Distribution Characteristics

the flow field distribution characteristic of diesel particulate filter (DPF) is very important to the regeneration. Taking the wall-flow honeycomb ceramic filter as an example, based on the k ƒ{ƒÕ turbulence, gas-particle flows and porous medium theory models, the velocity and the particulate concentration distribution field have been studied and analyzed during the DPF filtration. The results indicate that the vortex emerges around the small area wall when the flow passed the dilation pipe, but laminar flow inner the filter. And with the axis position increase, the axial velocity is more uniform distributed along the radial direction in all channels of the filter. The flow field uniformity will be good for the DPF pyrogenation regeneration. Particulate concentration distribution is very different in every radial channel along the axial direction. The particulate concentration is greater in the center area channels. It will cause the larger heat burden during the DPF regeneration, and influence the DPF working life. Therefore, it is very necessary to improve the interior DPF flow field distribution, in the paper, it is realized by the optimal design for DPF structure through adjusting the key dimension parameters such as diameter ratio, dilation angle etc.