[Bo3D]

I am simulating a wave tank to study wave runup on GBS structures. I have a wave boundary and outflow on the other end. I haven't had any luck so far. The fluid volume keeps incresing, up to 20% within 200 sec, and so as water surface elevations. Is this normal?

[MuxaB]

this does happen sometimes because the outflow boundary may not transmit the waves fully causing some to reflect and then ineract with the wave boundary itself. it may take somes experimenting with numerical options and resolution to improve the conservation of volume. The options may be different VOF schemes, mometnum advection order, pressure convergence level.