Quote Originally Posted by nikhsub1 View Post
What Vapor was saying is that no matter the position in the loop, each component will receive the same pressure and that is incorrect.
I never said that. I said that no matter where it is in a loop, it will have the same pressure drop--not that it will 'receive' the same pressure. I fully agree that pressure is not constant throughout a loop, each component (even tubing and fittings) has a given pressure drop at any flow rate.

If you're saying that position in a loop is a deterministic factor in pressure drop, then all the work that Swiftech, Thermochill, HWLabs, Martin, Koolance, Skinnee, et al have done with plotting pressure drop curves of their components is for naught.

But their work wasn't for nothing...at any given flowrate, a component has a certain pressure drop. There is no wiggle room with this. With that knowledge, a given set of components will have a combined net pressure drop (which is a curve, I agree that my 75-20-5 example was simplistic, but it's a lot easier to free-hand than using the actual curves) and with the PQ curve of a pump, you know the flowrate of the loop. Using the knowledge of the flowrate of the loop (which is constant throughout the loop), you know the specific pressure drop of every component and those values, again, do not vary depending on where they are in a loop.

EDIT: and pressure drop isn't a percentage function. It's a unit function.