| As an after-treatment device to reduce diesel engine particles emission, the diesel particulate filter(DPF) has the termly regeneration problem. Among the numerous regeneration technologies, the burner-type one has a cogent advantage for our specific national conditions, and has a good prospect in application. However, this technology requires an excellent flame stability and continuity of the burner. But there is few research of the flame characteristics that influenced by the burner itself, no matter at home and abroad. Therefor, the study on the stability and continuity of the burner flame that for the DPF regeneration will have certain and important practical significance.This research is based on the Graduate Student Innovation Project of Shaoyang University Hunan Province(CX2014SY016). A swirl-type burner was put forwarded for the DPF regeneration, the simulation and experiment were coupled to study the flow field and the regulation of flame stability and continuity that influenced by the main structure and operation parameters of the swirl-type burner. The main results are as follow:(1) Based on the steady characteristics of back-flow of swirl burner and the special of DPF’s porous medium flow, a swirl-type burner for the regeneration of filter was designed independently, and the fuel-air supply system, ignition system, main body structure was designed preliminary at the same time;(2) The simulation method was used to research the flow flied stability that effected by the structure and operation parameters of the swirl burner. The physical model was appropriately simplified, and the suitable turbulence and non-premixed combustion models were introduced, then the orthogonal experimental design method was adopted to research the regular of flow stability which influenced by the main structure and operation parameters such as length-diameter ratio, expansion ratio, the position of air supply pipe, air supply ratio, fuel supply ratio and the pressure in the combustor. The results show that: With an expansion ratio of 2.5, length-diameter ratio of 2.4 and center position on the combustor of the air supply pipe, the flow field combination property performs best. The air supply ratio effect most on the stability of flame, with the value of 5.97-6.63m/s and 50-70g/min fuel supply ratio, the flame shows a better stability; the pressure in the combustor has weak effect on the flame combustion situation unless it reaches very high. This conclusions provide references for the design theory of swirl burner and the practical application of DPF regeneration.(3) Took the ZD25 TCR High Pressure Common Rail Turbocharged diesel engine as the experimental platform, the DPF regeneration with swirl-type burner test bed was designed to collect the characteristic data of flame temperature, pressure in the combustor and the flow velocity and to verify the simulation results. The results show that, when the air supply rate is less than 5.97m/s, the experiment results have a poor match with the simulation, but once the air supply rate is greater than 5.97m/s, the experimental results can better match the simulation. At this situation, all the parameters such as temperature, flow rate and pressure can prove the tendency of the burn is more steady and adequately.This research provides a new way to design the burner for DPF regeneration, and has a reference value for the reliability and security of the burner improve. The use of dimensionless parameter design can better convenience for different specifications of diesel engine matching, which has a firm foundation for the popularization and application of the DPF regeneration with swirl burner. |
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