which BC for getting outlet pressure in a channel flow
 

Hi all, i have just started studying ansys fluent. what i have to find is the pressure drop in a microchannel with a specified velocity inlet and length of pipe. Nothing is known about outlet conditions. the outlet pressure need not be atmospheric. In such a case what should be my outlet boundary condition? how can i get the outlet pressure. when i m applying pressure outlet BC with zero gauge pressure i m always getting zero gauge pressure at outlet, but i need the actual pressure at outlet....somebody plz help me

Why are you interested in the absolute pressure at the outlet if you're aiming at the pressure drop in the pipe?r

sorry, now i understand even my question was wrong.....when i changed the outlet pressure values with pressure outlet BC the pressure drop remained the same. i m interested only in the pressure drop. But initially i thought wen i m fixing inlet velocity and channel dimensions i m fixing inlet pressure also....thats why asked such a question....do you want to add anything more?

Correct. You don't want to overcostrain your system. If you impose a pressure at the outlet the pressure at the inlet will be calculated in order to have a certain (imposed) velocity at that location.