(1) LNM, Institute of Mechanics, Chinese Academy of Sciences, Beijing, 100080, China;(2) College of Mechanical Engineering and Automation, Zhejiang Sci-Tech University, Hangzhou, 310018, China
Abstract:
The present paper describes experimental investigation on the flow pattern and hydrodynamic effect of underwater gas jets from supersonic and sonic nozzles operated in correct- and imperfect expansion conditions. The flow visualizations show that jetting is the flow regime for the submerged gas injection at a high speed in the parameter range under consideration. The obtained results indicate that high-speed gas jets in still water induce large pressure pulsations upstream of the nozzle exit and the presence of shock-cell structure in the over- and under-expanded jets leads to an increase in the intensity of the jet-induced hydrodynamic pressure.