Abstract:Cavitation phenomenon of the hole with instability, the generation of a hole and collapse induce the disturbance of fluid flow in the high-pressure spray hole, diesel injector nozzle hole Shigao pressure jet orifice of the typical form. By using the ANSYS software of fluent module, we simulate diesel injector under the different conditions of injection pressure, spray holes with different inlet rounded radii, diameter ratio inside the nozzle fuel hole shape, and we analyze the influence of the nozzle structure parameters on the fuel mass flow in the presence of cavitation. The results show that in certain circumstances, the injection pressure can be increased by increasing the inlet radius and changing the medium-diameter ratio as d/D<1.0 or d/D>1.1, which can inhibit the cavitation, and 1.0<d/D<1.1 can promote the cavitation. Increasing the inlet radius and the radius ratio of the nozzle can increase the mass flow rate of the fuel in the injection hole, and the effect is more obvious when the injection pressure is higher.
王鹏, 王忠, 瞿磊. 高压喷射喷孔结构参数对空化现象的影响[J]. 排灌机械工程学报, 2017, 35(12): 1063-1068.
WANG Peng, WANG Zhong, QU Lei. Influence of structure parameters of high-pressure jet nozzle on cavitation. Journal of Drainage and Irrigation Machinery Engin, 2017, 35(12): 1063-1068.
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