Outflow boundary in a wave tank
 

Dear all,
I read some articles and answer in this site about the non-reflection end boundary for a wave tank.

And I check the outflow boundary condition with allow fluid to enter at outflow boundary.
However, the volume of water in the wave tank still leakage from the tank.
Is there any option I should mention.

Thanks for your reading my problem.

split lagrangian vof method might help