Numerical simulation on interaction between cavitation and shock wave in compressible bubbly flows

The numerical simulation on the cavitating flow around an axis-symmetrical body in the steady compressible bubbly flow was simulated, and the interaction between cavitation and shock wave under different air volume fractions with the constant flow velocity and operating pressure was investigated. Firstly, to verify the used calculation model, the case which air volume fraction takes 0 in the incoming flow was calculated and shows a good agreement with the experimental result. Secondly, more cases with air volume fractions varying from 0 to 0.5 were calculated. The results show that with the increase of air volume fractions, flow field becomes more compressible. This result was confirmed by the appearance of three kinds of wave systems, including detached shock wave before the head, expansion wave at separation surface and oblique shock wave after cavity tail. The interaction between cavitation and shock wave is reflected as follows: bow shock before caviting region weakens cavitation effects, making caviting region decrease; cavity generated by cavitation results in occurrence of oblique shock; cavity closure point cannot locate on the body surface but on the shock surface, which can be confirmed by the adverse pressure gradient at the end of cavity. These results revealed a new physical phenomenon which existed in the interaction process between the cavity and the shock wave in compressible bubbly flows. © 2015, China Ship Scientific Research Center. All right reserved.