Re-reading the initial statement about forcing 64mm work of water through 50mm increases pressure is correct.
It increases pressure PUMP end, but the poster that kicked this all off believed it increased pressure BRANCH end which it does not. Tillerman confused static and dynamic pressure and the significance that each plays.
however what the initial comment meant was that if you had fixed pump pressure and branch flow rate on a 64mm line, and you restricted the flow (ie adding a 50mm working length) the pressure inside the hose would increase if nothing else changed. Same as when you knock off a branch, the pressure inside the hose increases (except on a smaller scale as the restriction in flow is minimal)
To maintain the flow rate with the 50mm as the second line then the PUMP pressure would need to be increased. The pressure at the end of the 64mm would increase but the pressure at the end of the 50mm (at the branch) would be the same for the same flow rate, not higher as stated by the original post.
In lay terms, to achieve the same volume: the smaller the hose, the higher the pressure.
to achieve a flow rate of 400GPM in 50mm hose, Pressure would have to be 800kPa.
This is based on a branch with fixed flow rates, non adjustable etc (as in basic, hick)
You are perfectly correct there and consistent with my previous posts being that the pressure PUMP end needs to be higher to get the same amount of water out the other end. This however does not result in higher pressure at the BRANCH end for the same volume flow.
I am also familiar with fluid mechanics my friend
Congratulations.... even though you do seem a little lost. Its covered in most science, maths and engineering courses so its not exactly difficult to come across while studying.
you have not only made your self seem like a jerk, but actually shown your stupidy in not being able comprehend the initial meaning of the statement. Brainiac...
well my initial statement was:
"So the hose increases pressure? There I was thinking it was the pump."
And that is still 100% correct. You can have all the hose you want, but the pressure/flow/energy comes from the pump (neglecting gravitational effects).
Next I quote for you what tillerman said:
Well i don't know about you but i thought when you force 64mm worth of water into a 50mm hole the water would have to speed up therefore giving you more pressure at the tip...
I didn't think you could miss comprehend that, but you are from Burnside. If you know fluid dynamics like you say you do, then you should know that statement is incorrect. Pump end pressure increases but "tip" pressure remains the same for the same flow rate.
I put it to you that you have over simplified the problem and not only made your self seem like a jerk, but you've actually shown your stupidity (not to mention miss spelling stupidity) in not being able comprehend the initial meaning of the statement.
