Qualitative and quantitative analysis of interaction between cavitation patterns and vortices of a pitching hydrofoil from Lagrangian viewpoint

The evolution of transient flow structures and mass transport in cavitating around a pitching hydrofoil is investigated qualitatively quantitatively, the interaction between cavitation patterns vortices elucidated from Lagrangian viewpoint. First, turbulence effects are estimated by density-corrected k–ω model to account for local compressibility multiphase at Reynolds number Re=6.4×105. Then, formation vorticity during whole cycle analyzed using averaged deviation method. By comparing hydrodynamic properties varying angles attack, divided into two distinct stages, namely multi-scale cloud phase α+=10° α−=8°, traveling sheet α−=8° α+=10°. Specifically cavitation, pattern closely related development main vortex. Furthermore, quantitative analysis method based on network developed deeply analyze mixing processes. Importantly, coherence ratio parameter proposed as indicators precisely quantify spatial connectivity behavior. Finally, correlations vapor fraction, codelength, global evaluated. As conclusion, it shown that methods powerful tool both qualitative analysis, results obtained could provide key important understanding structure changing mechanism marine hydro propulsion systems.