Hydraulic total pressure

1. Nov 12, 2011

Yuri B.

Total pressure is a sum of the static pressure and the dynamic one, and is said to be the same along a pipe/duct.
In the water pipe gauge (static) pressure is maximal after the pump and minimal at the pipe outlet, but the speed and the density being the same, the dynamic pressure is the same everywhere. So, the total pressure is different at different points ?

2. Nov 12, 2011

Staff: Mentor

Yes: In a real-world situation, the stream of water loses energy as it flows, due mostly to friction and viscous losses. This is why pumps require input energy.

3. Nov 12, 2011

maxx_payne

russ_watters EXCELLENT

4. Nov 12, 2011

Yuri B.

Does total pressure stay the same everywhere in a closed system ?

5. Nov 12, 2011

256bits

Not according to Russ.
The loss as the flud moves down the pipe is called, well, head loss.

6. Nov 13, 2011

Yuri B.

The TP at discharge is not = the TP at suction ?
Why ?

7. Nov 13, 2011

Staff: Mentor

That's the entire purpose of a pump.

8. Nov 14, 2011

maxx_payne

because u give the pump electric power and it transimits it to hydraulic power
thats the reason YURI

9. Nov 14, 2011

Yuri B.

I got it so: the first statement (in my OP) - which one can meet not once in the writings on the subject - is true conditionally for only short lengthes of a system where head losses are considered negligeable.
Thank you!

10. Nov 14, 2011

maxx_payne

my friend we always here neglect secondary losses like fittings and valves but length no and also it depends on the length ur talkin abt