- #1
MarleyDH
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Homework Statement
Water is flowing from left to right through the system shown below. If the reading on
the pressure gauge is 384 kPa, what is the power input from the pump? Ignore energy
losses.
Homework Equations
Conservation of Mass (Q = vA)
Bernoulli's Equation (Total Head = Elevation Head + Pressure Head + Velocity (Kinetic) Head)
Manometry (Pa = Pb)
The Attempt at a Solution
I figured that you can use the Pressure from the pressure gauge to get the pressure in the venturi, but beyond that I am lost.
I'm guessing because the diameter [of the pipe] before the pump is the same as the diameter directly after it the velocities will be equal. (v1 = v2)
The pressure before the pump should in my mind be negative as the flow is from left to right. This can also be seen with the manometer on the left hand side, the mercury is higher on the left tube than on the right tube, indicating suction (vacuum).
This however is where I get stuck. I can't see past this point, as I need the velocities to calculate the differential in head so as to calculate the power of the pump.