High-Speed Imaging of Water Hammer Cavitation in Oil–Hydraulic Pipe Flow

A pipe water hammer with column separation was studied in a range of flow rates (Re=465 to 2239) test rig an acrylic glass observation section. Pressure transients were measured piezoresistive pressure sensors, while the gas evaporation and condensation captured by high-speed recording Photron SA-Z at frame rate 75,000 fps. Separation lengths estimated threshold value images. The results did not show sharp gas–oil interface but consisted small, dispersed bubbles mixed larger vapor structures, where seemed become smaller after each collapse. These findings differ from transient cavitating characteristics commonly reported nonhydraulic piping systems governed different fluid properties time scales. Good repeatability, both terms bubble distribution, observed. quantified as metric length, which consistent between tests. Combined measurements, these may assist obtaining better understanding cavitation dynamics within oil–hydraulic well be used improve modelling strategies towards more accurate erosion predictions.