An experimental investigation has been carried out to evaluate the performance of a cavitating Venturi flow. For that purpose, a closed loop circuit with a centrifugal pump and a transparent asymmetric converging-diverging test section has been built which allows to set the pressure level and the flow rate. The system is instrumented with several pressure sensors and temperature probes that are continuously monitored during the tests. The experiments have consisted in generating non-cavitating and cavitating flows inside the Venturi under controlled conditions. The obtained results, which have been characterized as a function of the Venturi's discharge coefficient, pressure ratio and pressure loss coefficient, are in good agreement with previous studies carried out with standard Venturi geometries, specially under non-cavitating flows. The Venturi's performance under cavitation flows has been found to be dependent on the Venturi's inlet pressure and similar to a chocked flow condition with constant volumetric flow rate. On the basis of these observations and the analogous behaviour with compressible gas nozzles, a new flow coefficient has been derived which remains constant at any cavitating regime. Thus, this coefficient permits to use a Venturi as a flow meter on cavitation conditions.

已经进行了实验研究以评估空化文丘里流的性能。为此，建立了带有离心泵和透明的不对称收敛-发散测试部分的闭环回路，该回路允许设置压力水平和流量。该系统配备了多个压力传感器和温度探头，在测试过程中会对其进行连续监控。实验包括在受控条件下在文丘里管内部产生非空化和空化流。所得结果已被表征为文丘里管排放系数，压力比和压力损失系数的函数，这与以前对标准文丘里管几何形状进行的研究非常吻合，特别是在非空化流下。已发现文丘里管在空化流下的性能取决于文丘里管的入口压力，并且类似于具有恒定体积流量的阻塞流情况。根据这些观察结果和可压缩气体喷嘴的类似行为，得出了一个新的流量系数，该系数在任何空化状态下都保持恒定。因此，该系数允许在气蚀条件下使用文丘里管作为流量计。