[shouvik ghorui]

Hello, everyone, I am new in OpenFOAM, I am trying to simulate a negative pressure ventilation room.there is a present and a bed inside the room and the present release constant heat flux. for creating the negative pressure inside the room. I want to give an inlet and outlet as a pressure boundary condition. for inlet, I will give 0pa and for the outlet -8pa.
and I use buoyantPimpleFoam
now the question is
1) can I use both pressure boundary condition at inlet and outlet?
2) in which file(p or p_rgh) I have to specified value of pressure -8pa?
if any data is required to say then, please let me know. thanks in advance. if anyone helps me it will be great for me.