Graphic Visualization of Simulated Downstream Wakes Generated by Various High-Speed Hull Forms.

摘要

The downstream turbulent wakes of surface ships are numerically simulated by the parabolic marching computer code SURFWAKE. This code solves the incompressible time-averaged Navier-Stokes equations with a two equation (K, epsilon) closure model for the turbulence, and a rigid-lid approximation to the free surface. Graphic software are developed for two and three dimensional visualization of the results for velocity, turbulence kinetic energy and Reynolds stress. These programs are designed for user-friendliness and compatibility with the output of SURFWAKE. Results for the following three ship models are presented: a twin-screw (inward-rotating) frigate, a single-screw frigate, and a twin-screw (inward-rotating) containership. Visualization of these results bring out several interesting features of the numerical simulation. We have attempted to distinguish wake characteristics based on the hull features. Simulation over a large distance downstream for the single-screw frigate reveals that the propeller wake does not rise to the free surface.