摘要
为了研究旋涡空化所引起的空蚀和振动观象以及二者的关系,采用高速摄影的方法,观察了发生在射流放水阀山部的空化形态。采用快速富里叶变换（FFT）分析了空化所引起的振动。采用失重法,进行了空蚀实验。结果表明,旋涡空化能引起严重的空蚀和剧烈的振动。在旋涡空化发展的个同阶段,其所导致的振动和空蚀呈观了个同的特性。当Sσ>0.74时,随空化数的变化,振动和空蚀呈现了相同的变化趋势,但是,在0.50<σ<0.74的范围内,振动和空蚀呈现了相反的变化趋势。这是由于水流中空化旋涡的数目和形态随空化数的变化,以及旋涡空化引起振动和空蚀的机理不同所造成的。
To make clear the characteristics of erosion and vibration induced by vortex cavitation in different cavitation conditions, and the relations between the two phenomena, cavitation aspects around a hollow-jet valve are observed by a high-speed photograph. Vibrations induced by cavitation occurred around the valve are measured by using a accelerometer mounted on the valve wall. Erosion experiment is also conducted in different cavitation conditions. It is found that both the vibration and erosion appeared different characteristics in different cavitation development stages. Especially, in a transient cavitation stage, the intensity of vibration increases with the decreasing of cavitation number, however, the intensity of erosion, that is the mass loss on the surface of a eroded specimen, decreases with the decreasing of cavitation number.
出处
《工程热物理学报》
EI
CAS
CSCD
北大核心
2002年第6期707-710,共4页
Journal of Engineering Thermophysics
基金
教育部留学回国人员科研启动基金资助项目
