Cavitation Scale Effects for Valves

Proper use of experimental cavitation data for valves requires adjustments for scale effects including the influence of valve size and operating pressure. Incipient and critical cavitation data obtained on a small valve tested at a low pressure must be adjusted when used to predict the performance of a larger valve operating at a higher pressure. Empirical equations are presented for making size and pressure scale effects adjustments. The equations were developed from experimental data collected on numerous types and sizes of valves tested over a range of pressures encompassing most valve applications. Comparisons of the predictions with experimental data show that the accuracy of the adjustment is of the same order as the accuracy in determining the incipient or critical cavitation condition from experimental data.