Dynamic Behavior And Measurement Of Cavitation Bubble Collapse Near Slender Sticks Tip

Cavitation occurs naturally and in many engineering processes,such as fluid machinery internal flow,and has a distinctive dynamic process that has gotten a lot of interest and is a hot research area in hydrodynamics.The research presented in this paper on the cavitation bubble collapse process is extremely important,whether it is to alleviate the cavitation problem produced by cavitation bubble collapse or to improve the application of laser cavitation strengthening technology on the surface of materials.In this paper,the dynamic characteristics of cavitation collapse near the end faces of single and double filaments are studied by combining experiments and numerical simulations.Use laser-induced cavitation and high-speed camera to capture the process of cavitation collapse.The collapse shape of the cavitation near the end faces of single and double filaments and the influence of dimensionless parameters on the collapse of the cavitation are discussed.The VOF model was used to simulate the collapse process of single and double filament end face cavitation,and compared with the experiment,the results show:(1)The entire process of cavitation collapse can be split into three typical forms when it occurs on the end faces of single and double filaments,and the crucial parameters of each morphological change can be derived.(2)When the dimensionless near-wall distance γ =0.37、0.56,the distance to the single filament’s end face is relatively close,and the cavitation collapse jet’s velocity is not at its maximum.The greatest jet velocity can reach 300m/s When γ=0.74.(3)When the cavitation collapses near the end face of the double filament,the cavitation presents a symmetrical collapse shape up and down and impacts the end face.The pressure load on the end face increases first and then decreases with the increase of η,and the maximum pressure load can reach 10 MPa.