I am modelling a body in a 3d mutliphase domain, of water at the bottom and air on top, I am interested in the drag forces on the body which is partially submerged. my velocity inlet is 2 times the length away from the body and the outlet is 4 times length away, I am getting a lot of back flow and the mass flux is very highly positive. I am using symmetry through my body and all other boundaries are over 1L away from the body
Any suggestions on ways to reduce the backflow? Ideally zero backflow but that is not always possible, I have attempted to use both outflow and pressure-outlet. I am using the student software more or less to capacity on the number of nodes so very restrained on adding any additional length to the domain.
Thanks in advance!