In hydrodynamics, the inertial cavitation occurs when the speed of fluid changes drastically at a small distance, which leads to reduced local pressure. Cavitation is, in most cases, an undesirable phenomenon, the effects of which are erosion, excessive noise, vibration, and flow disorder. We discussed the occurrence of cavitation in a test model with a small nozzle, which we designed for the needs of major foreign company. The model allowed us to record the formation of cavitation with a fast camera. Obtained images were then examined and processed with a computer. The results were presented in the form of contour diagrams for the mean value of the greys, the standard deviation of the greys and in the form of frequency diagrams. We analysed the velocity of shock waves and looked for repeatable patterns in the dynamics of cavitating fluids. We found that the spread of cavitation is dependent mainly by the exit pressure from the nozzle, which also affects the rupture frequency of cavitation structures, in which the pressure drop causes a decrease in the frequency. By analysing shock waves, we found that its behaviour was rather chaotic, unpredictable, and without any patterns, which achieved speeds up to 400 m /s. In the analysis of the "cavitation flower" we observed the presence of a pressure wave on the edge of cavitation and its effect on the collapse of cavitation structures.
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