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agondouin
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This is not a homework problem but I'm going to try and present it like one.
1. Water is flowing through a horizontal, open-ended pipe, of constant diameter. A pump is mounted upstream and the water flows through the pipe. The pump supplies a gauge pressure of 20 psi and the flow rate is 8 gpm. A larger pump is used to increase the gauge pressure to 80 psi. What is the flow rate?
2. I tried to use Bernoulli's equation: P/rho + 1/2*v2 + gz = constant
3. I tried to apply Bernoulli's equation to two points in the pipe, after the pump and at the pipe outlet. P1 is the upstream pressure with the small pump. P2 is the upstream pressure with the big pump, and Pe is the pressure at the pipe exit. I think Pe is atmospheric pressure.
I get: P1-Pe = rho(ve2-v12), and P2-Pe = rho(ve2-v22)
Then I tried dividing these two. So I got:
Pgauge 1/Pgauge 2 = (ve2-v12)/(ve2-v12)
I'm not sure what to do after this, or if I've done this right so far.I must be missing something. Any help is greatly appreciated
1. Water is flowing through a horizontal, open-ended pipe, of constant diameter. A pump is mounted upstream and the water flows through the pipe. The pump supplies a gauge pressure of 20 psi and the flow rate is 8 gpm. A larger pump is used to increase the gauge pressure to 80 psi. What is the flow rate?
2. I tried to use Bernoulli's equation: P/rho + 1/2*v2 + gz = constant
3. I tried to apply Bernoulli's equation to two points in the pipe, after the pump and at the pipe outlet. P1 is the upstream pressure with the small pump. P2 is the upstream pressure with the big pump, and Pe is the pressure at the pipe exit. I think Pe is atmospheric pressure.
I get: P1-Pe = rho(ve2-v12), and P2-Pe = rho(ve2-v22)
Then I tried dividing these two. So I got:
Pgauge 1/Pgauge 2 = (ve2-v12)/(ve2-v12)
I'm not sure what to do after this, or if I've done this right so far.I must be missing something. Any help is greatly appreciated