At an opening in turbulent flow, using wall boundary condition, with constant flow rate and constant pressure inlet, would be similar to an opening with inflow BC?
Here I'm trying to answer whatever I could figure out from the question " Is a wall with constant inlet pressure and constant inflow similar to an opening ? "
As per the classical fluid mechanics / fluid dynamics no opening can ever simulate a wall or a confined volume of fluid despite the fact that the fluid is at constant inlet pressure and constant inflow since although the opening is at a constant inlet pressure / inflow still there exists certain pressure above the datum which can't simulate the inflow boundary conditions.
The lower edge of a hypothetical inviscid fluid of uniform velocity that has the same flow rate as occurs in the real fluid with the boundary layer experiences a pressure & a velocity gradient as well.
Be it the point where the velocity profile essentially reaches the asymptotic velocity as the boundary layer thickness ( velocity boundary layer thickness, displacement thickness or the momentum thickness ), its impossible to define an exact location at which the velocity profile reaches the asymptotic velocity in a boundary in the case of an inflow irrespective of the laminar / turbulent flow ( based on physiological occurrence or direction of flow ).
Well, If I define a constant flow rate, and constant pressure as boundary conditions for a wall-type boundary in my simulation, would the result for velocity and pressure field be similar to that if i define the same BC but this time change the boundary type to inlet-type?
I still do not understand your question, if you have a wall boundary condition, the pressure on the wall is a result of your flow condition, you cannot set it. And what do you mean for a constant flow rate on a wall?