Numerical Studies of Turbulent Free Surface Flows and Unsteady Propeller Flows

摘要

Two main problems have been studied, viz. the structure of turbulence near a freesurface and the Reynolds-averaged solution of unsteady propeller/hydrofoil flows by the renormalization group (RNG) two-equation turbulence transport model. A variety of free-surface turbulence simulations demonstrate the key modifications in turbulence structure due to the free surface. In addition, we determine the modifications in surface wave spectra due to the turbulence beneath the free surface as typically represented by a renormalized dispersion relation. The results for unsteady hydrofoils show the power of the RNO method in robustly and accurately treating large-scale unsteady and transitional flows, a marked improvement over previous turbulence transport models. (AN).