Quote:
Originally posted by ECUPirate
here's my two cents...
Regarding your last question about the weight of the water - for the lengths of tubing in a puter system
What goes up must come down. If you have a vertical loop of water, and you try to move the water around the loop, wouldn't the weight of the water moving up be balanced by the weight of the water falling down? Yes, initial inertia (like that?) would be greater, but once you got it moving.... I don't think there'd be much difference between a vertical loop and a flat (horizontal) loop.
I thought head meant vertical lift w/ the tube open on the top end. (the ability of the pump to lift water w/ no return.
Your thoughts??
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Yeah that's true.
Also note that pumps pump a constant volume per unit time. So if your cross-section increases your speed decreases, but volume pumped remains the same (this is of course ignoring head loss due to friction).
Examining head loss due to friction, you need to look at the cross-section and examine the circumference (where surface tension resists the flow) and the area. You need to examine the relation of area per unit circumference. Since circumference of a circle is 2(pi)radius and its area is (pi)(radius)^2, it is obvious that if the circumference is increased linearly, the cross-sectional area increases in a quadratic manner, meaning that area per unit circumference increases as circumference increases, thus reducing friction per unit area.