interFoam current, Why Water Level decreases in time
 

Hello,

I am building a 2D simuation of a wave flume, I try to work only with current and a berm as can seen in the figures I attached. The goal is to work with a steady current of 0.49 m/s and a water depth of 0.75 m. I am using .com version.

The problem is after a longer simulation the WATER LEVEL DECREASES IN TIME, I added a few printscreens of the simulation. :confused:

I think there is something wrong with my boundary conditions, I added them as well. I am using a laminar model.

I work with two inlets to hold the water level constant and to keep the velocity uniform over he inlet which is only water.

Can anyone help me? Or does any one have any suggestions?
Thanks in advance.

PS: I want to set my BC in boxes here but I don't know how to that either.

Here are some extra printscreens