If a pipe flowing with water enters a structure where the structure wall will stop the horizontal velocity of the flow and direct it downward (i.e a pipe in to a manhole with an outlet at a considerably lower elevation), how do you calculate the force exerted on the structure of that wall. I have found the equation Force = density of water * flow volume * change in velocity. Is this on the right track?
Welcome to PF! Hi smprindi ! Welcome to PF! Yes … from good ol' Newton's second law … force = rate of change of momentum = velocity times mass per time … which is the same as your Force = density of water * flow volume * change in velocity.