Effect of wavy leading edge on hydrofoil-turbulence interaction noise

In order to solve the underwater noise pollution and improve acoustic stealth performance of vehicles, NACA0020 was bionically modified according structure leading edge tubercles humpback fin. The flow field characteristics hydrofoil-turbulent interaction model before after modification were studied by using large eddy simulation FW-H equation. results show that wavy can effectively reduce turbulence hydrofoil, especially broadband 89.55 Hz. overall sound pressure level(OASPL) directivity hydrofoil are same as original both have dipole characteristics, but value in all directions is reduced a certain extent. OASPL calculated analyzed different frequency bands. has best reduction 1 000-5 000 Hz band, be up 12.6 dB. Through analysis field, it concluded effect mainly relates decrease fluctuation at coherence vortex spanwise direction caused enhancement flow.