The turbulent viscosity of the RNG k-e model is modified based on the filterbased density correction mode(FBDCM)model,and the cavitation model is modified by considering the influence of shear stress on cavitation formation.Compared with the experimental results,the accuracy of the simulation model is verified.The geometric model of the central body cavitation nozzle is established,and the effects of expansion angle,contraction section,throat section,expansion section and center body retraction distance on cavitation performance are studied.The results show that the expansion angle,the expansion section and the center body retraction distance have a great influence on the cavitation performance.Through in-depth research,it is found that the change of jet velocity caused by the structural parameters leads to the change of the thickness of the jet shear layer,which affects the distribution of the low-pressure area of the flow field,resulting in different sizes of cavitation clouds in the jet flow field.It has been found that the nozzle cavitates best when the contraction cross section is 4 mm,the throat cross section is 4 mm,the expansion cross section is 5 mm,the expansion angle is 60°,and the centre body indentation distance is 1 mm.
关键词
中心体空化喷嘴/参数优化/空化射流/数值计算
Key words
central body cavitation nozzle/parameter optimization/cavitation jet/numerical simulation
维普
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