by Guest » Wed Nov 07, 2007 10:17 am
On the diaphragm, you forgot to multiply by the area. The actual force (when just beginning to open) is 2.43 lb.
The x is the preload of the spring, which you didn't give.
Once the valve begins to open, you have a very complex flow situation, and you will have to look at dynamic pressure in the flow (Bernoulli's equation). Since I'm an electrical engineer, that's beyond what I can do with a flow problem. I don't know how to calculate the fully open situation.