I am tasked to design an orifice plate to be inserted into a water tunnel in an experiment. I am having some problem with the force calculation. To understand the amount of pressure being applied onto the plate, the dimensions of the orifice is known. P = F/A A is known therefore I need to calculate what is F. F = ma I am not sure can I use m = density x area x velocity If it is correct, how do I determine what is the acceleration? Once the velocity of the water is being regulated and remain constant, it will means that the acceleration is = 0. Will need some help here. Thanks alot!