This paper deals with visualization and velocity analysis of a self-excited water jet generated by a designed prototype of hydrodynamic nozzle. The high-speed camera in combination with four high-energy pulsed LED lights and the particle image velocimetry method were tested. The influence of water pressure on the jet shape, velocity field and frequency of the self-excited jet was studied. The designed diagnostic water line consisting of pressure sensors and a turbine flowmeter was used for flow monitoring during experimental flow visualization. It was observed that the used optical equipment is suitable for velocity-frequency investigation up to 40 MPa with the maximal jet velocity 247 m/sec, 4.5 kHz oscillation frequency. The overall speed dependence of velocity on the distance downstream from the nozzle outlet (0–100 mm) decreases by 13–15% for tested pressure levels. Oscillation of self-excited jet in the 10–40 MPa pressure range is changing in range 2.5–4.5 kHz.

本文研究了设计的流体动力喷嘴原型产生的自激水射流的可视化和速度分析。测试了结合四个高能脉冲LED灯的高速相机和粒子图像测速方法。研究了水压对自激射流形状，速度场和频率的影响。设计的诊断水线由压力传感器和涡轮流量计组成，用于在实验流量可视化期间进行流量监控。观察到，所使用的光学设备适用于最高40 MPa的速度-频率研究，最大射流速度为247 m / sec，振荡频率为4.5 kHz。在测试压力水平下，速度对喷嘴出口下游距离（0-100 mm）的整体速度依赖性降低了13-15％。在10–40 MPa压力范围内，自激射流的振荡在2.5–4.5 kHz范围内变化。