20.500.12556/RUL-117685 Visualization and measurements of shock waves in cavitating flow Upon cavitation cloud collapse an omnidirectional shock wave is emitted. It then travels through the flow field, causing a cascade of events resulting in erosion, noise, vibration and the cavitation shedding process. Despite that the accumulated data points evidently to the presence of the shock waves, the direct measurements hardly exist - and even then, they are very expensive and time consuming to perform. In the present paper, the possibility of detecting shock waves inside cavitating flow is shown. The methodology bases on using two conventional high speed cameras. With the first one cavitating flow from a distance is observed, determining the position of the wave, while the second camera with a microscopic lens enables a close-up view to determine the number and size change of air bubbles as a shock wave passed them. By calibration and reference measurements the amplitude of the shock waves was determined. This relatively simple approach enabled the first observation of shockwaves which occur at the cavitation cloud collapse (downstream of the attached cavity). Several examples of shock wave dynamics are shown and how they influence the general cavitation cloud behaviour. Shock wave front velocities and local pressure waves caused by cloud collapse were estimated from visualization, reaching values to more than 700 m/s and over 5 MPa respectively. cavitation shock waves high speed video cloud collapse kavitacija udarni valovi visokofrekvenčno snemanje kolaps kavitacijskega oblaka true false true Angleški jezik Slovenski jezik Članek v reviji 2020-07-21 13:07:26 2020-07-21 13:07:32 2022-08-30 03:59:36 0000-00-00 00:00:00 2020 0 0 10 str. art. 110215 Vol. 119 Nov. 2020 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 532.528(045) 0894-1777 10.1016/j.expthermflusci.2020.110215 23172099 170523 RAZ_Petkovsek_Martin_2020.pdf RAZ_Petkovsek_Martin_2020.pdf 1 14DD6282D3B862A77615F6C7E0FE3F11 b9552214f995e6b4f0406d524bca372c5c2c7a22fe7075b919da981fd0d8436d 3d4afc58-a1b9-11eb-a523-00155dcfd717 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=131575 https://www.sciencedirect.com/science/article/pii/S0894177720307196 0 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=131573 Fakulteta za strojništvo 0 0 0