Numerical Investigation of the Turbulent Cavitating Flow over Submerged Bodies

抄録

A numerical method for the calculation of turbulent cavitating flow over submerged objects is proposed in present work. Cavitation is modeled via a single-fluid cavitation model which is derived based on a truncated form of the Rayleigh-Plesset equation and the mixture multiphase theory. The approach has been implemented by user-define function which is widely used in ANSYS FLUENT. Detailed results are presented for sheet cavitation over a submerged hemispherical object in a wide range of cavitation numbers and the cloud cavitation around a Clark-Y hydrofoil. In particular, for the hemispherical body, we compared the surface pressure distribution with experimental data which was available in literature. Later the cloud cavitation structure and its effect on the forces of the hydrofoil were studied. The comparisons between the simulating and experimental results show that present numerical approach has good capability to predict the surface pressure coefficient and the pulsation frequency at cavitation number σ=0.4, 0.55 and 0.65 of the hemispherical body under cavitation conditions. Meanwhile, for the hydrofoil, the proposed approach is sufficiently robust to predict the characteristics of the time-averaged lift and drag coefficients and the evolution of the cloud cavity with time.