Damping absorption of numerical wave tanks in hypergravity field
WANG Qiao-sha;LI Ming-hai;ZHANG Ling-yun;China Academy of Engineering Physics Institute of System Engineering;
In this paper, the Reynolds averaged N-S equations and RNG k-? equations are solved for establishing the viscous numerical wave tanks. The problem of damping absorption in Ng force field is studied in the viscous numerical wave tanks. Three damping functions for describing the variation of the damping in damping zone are presented and studied. The results show that for the case with small wave steepness, the damping function 1 with the linear increasing of damping has a clear advantage. However, with the increase of wave steepness the influence of too fast growth rate of damping, at the front of the damping zone, can not be neglected. And the damping function 2 and 3 with the nonlinear increasing of damping have the opposite quality. The damping coefficient can be set to N×103 in Ng force field when the same damping function the reflection coefficients are basically similar in different accelerations of body force. The scale considered in hypergravity field is from1/25 to 1/50 at the sea state level about 3~4 for the limitation of the dimensions of the wave tank. And the smaller scale should be considered for the simulation of the extreme sea state.