摘要：A steady and unsteady single-phase level set method is being developed for the
RANS code CFDSHIP-IOWA to simulate free surface flows around complex geometry
with large amplitude motions and maneuvering. A structured overset grid approach
is used to allow flexibility in grid generation, local mesh refinement, and to
efficiently resolve incident waves. The overset interpolation coefficients are
computed with the software packages Pegasus (from NASA) or Suggar (from HPC
PET). Dynamic interpolation is achieved through interfacing CFDSHIP-IOWA with
Suggar, allowing for the simulation of moving objects and enabling the
computation of moving hulls, rudders, etc. while maintaining good grid quality
in the far-field. We show examples of high speed-flows exhibiting breaking bow
and transom waves and a high-amplitude rolling surface combatant. High-speed
ships are of increasing interest for diverse applications including fast
commuter services, fast ferries, fast cargo ships, and fast combatants requiring
innovative hull designs and propulsion systems. The method is demonstrated for
two high-speed hulls showing overturning waves: the surface combatant DTMB 5512
and the R/V Athena patrol boat. Comparison of numerical results with
measurements shows that the method is able to accurately simulate the
overturning bow wave, resulting free-surface vortices, and boundary layer.
Several splash-ups can be captured if the grid refinement is appropriate.
Dynamic overset grids are demonstrated for a coupled pitching and heaving bare
hull surface combatant at medium and high Froude numbers in head waves.
