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预测水力机械和装置中绕流构件的空化特性，是在空化试验设备中进行模型试验的目的，然而尽管采用了谨慎的测试方法和半经验的比尺关系，试验结果的分散性仍然较大。近年来，在对空化初生的比尺效应进行大规模试验研究的过程中，试验液体的抗拉强度受到特别重视。试验清楚地表明，在未考虑水质的情况下，空化试验结果，尤其是初生空化试验的结果分散性较大，据此既不可能确定绕流物体的特征值，也不可能推导出初生空化的比尺关系。通过精确控制空化试验中试验用水的抗拉强度，可以清楚地得出普遍适用的速度、尺寸和粘性比尺影响的简单关系。
Predicting the cavitation characteristics of flow-passing components in hydraulic machinery and installations is the goal of model testing in cavitation test equipment. However, the discrepancy of the test results is still comparatively high despite the careful test method and semi-empirical ratio scale Big. In recent years, in the process of large-scale experiment on the scale effect of cavitation primary, the tensile strength of the test liquid has received special attention. The test clearly shows that without considering the water quality, the results of the cavitation test, especially the results of the primary cavitation test, are quite dispersive. Therefore, it is impossible to determine the eigenvalue of the flow around the object and it is impossible to deduce the initial Cavitation scale relationship. By precisely controlling the tensile strength of the test water used in the cavitation test, it is clear that the universal relationship between speed, size and sticking effect of the scale is clearly established.