I'm trying to resolve the Streamlines "deformation" provoked by the object, the idea is to simulate a turbulent flow in a gutter and see how much the Streamlines deform in the vertical direction, and how much the cavity grows, and if it is independent of the flow inlet velocity and how it varies from an object with a rectangular shape to a semicircular shape and triangular shape (Keep in mind I don't want to make a multiphase simulation). As u mention I think I might be making huge mistakes in my BC's and yes my inflow is uniform, sorry for my lack of knowledge in this area I'm pretty new at CFD in general and also for my grammar and spelling, and thank you for ur time!