壅塞空化器空化噪声实验研究  

Experimental investigation of cavitation noise produced by choking cavitator

作　　者：张凤华[1] 徐俊超[1] 苏新[1] 李念[1] 唐川林[1] 

机构地区：[1]湖南工业大学机械工程学院,湖南株洲412007

出　　处：《水动力学研究与进展（A辑）》2015年第2期160-166,共7页Chinese Journal of Hydrodynamics

基　　金：国家自然科学基金(51374101);湖南省自然科学基金(2015JJ5014)~~

摘　　要：为了避免水力机械产生空蚀破坏,目前对空化噪声的研究主要集中在空泡的初生问题,而为了有效利用空泡溃灭能量,研究空化时空泡溃灭强度的报道却较为少见。该文在不同背压下,利用水听器对不同壅塞管直径的壅塞空化器测试空化噪声信号,采用声压级差法和噪声能量比值法分析测试结果,探索壅塞管直径和背压对壅塞空化器空化特性的影响。结果表明:空化噪声信号的声压级差法和噪声能量比值法分析的结果基本一致,壅塞空化器在背压孔当量直径d=3.5―6.0 mm的背压范围内,都会产生明显的空化;不同壅塞管直径的壅塞空化器产生强烈空化都有相应的最佳背压范围,且随着壅塞管直径的增大,最佳背压范围会逐渐缩小;在最佳背压范围内,壅塞管直径和背压的变化对壅塞空化器产生的空化强度影响较小。研究成果完善了壅塞空化器设计的理论基础。The researches of cavitation noise mainly focused on the incipiency of cavitation in order to prevent the generation of the cavititation erosion in the hydraulic machinery, while there were few reports about the collapse strength of cavitation bubbles in cavitation study to utilize efficiently the collapse energy of cavitation bubbles. In this paper, the cavitation noise signals are collected with hydrophones for the choking cavitator having different diameters of choke pipe under the different back-pressure, and are analyzed by the sound pressure level method and the noise energy ratio method. The effect of the choke pipe diameters and the back-pressures on the cavitation characteristics of chocking cavitator is explored. The results show that the analyzing results for the cavitation noise signals with the sound pressure level method are in good agreement with the noise energy ratio method. The chocking cavitator can produce the obvious cavitation when the equivalent diameter of back pressure hole is 3.5 mm-6.0 mm, and has the different best ranges of back pressure corresponding to the different diameters of choke pipe for producing the strong choking cavitation. As the diameters of choke pipe increase, the best range of back pressure gradually reduces. Within the best back pressure range, the effect of the changes of the choke pipe diameter and back pressure on the cavitation strength produced by the chocking cavitator is small. Research results perfect the theoretical basis for the design of chocking cavitator.

关 键 词：空化 壅塞 壅塞空化器 空化噪声 

分 类 号：TV131[水利工程—水力学及河流动力学]