为了研究旋涡空化所引起的空蚀和振动现象以及二者的关系,采用高速摄影的方法,观察了发生在射流放水阀内部的空化形态.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.在旋涡空化发展的不同阶段,其所导致的振动和空蚀呈现了不同的特性.当σ＞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.
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