Calculating mass flow rate while assuming shock losses

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1. Aug 2, 2016

Taylor0304

Below is a 2 part question regarding gravitational pipe flow, I have managed to do Q1) and have got an answer of 144 kg/s. However Q2 asks that shock losses be considered, Although I know how to calculate the shock pressure loss I am unsure of how to apply this to my calculation to get a new mass flow rate value, an explanation would be great, thanks.

1. The problem statement, all variables and given/known data

Q1) Water flows through a pipe from one reservoir to a lower reservoir. The difference in height of the water levels in the reservoirs is 1.5m. The pipe is 0.5km long with a constant internal diameter of 400mm. It has a surface roughness of 0.20mm. Determine the mass flow rate of water. You may assume negligible shock losses. You will need to iterate to find a solution.

Q2) Repeat Q1 but allow for shock losses in the pipe. Assume that total shock losses (pipe
inlet, outlet and all pipe connections and valves) are equal to 5 times the velocity pressure
in the pipe.

2. Relevant equations

Bernoulli equation
Darcy equation

3. The attempt at a solution
I believe the change in pressure is 3270pa but I'm not sure how to apply this to get a new mass flow rate value.

rho/2 x C^2 = 1000/2 x 1.144^2 = 654
654 x 5 = 3270Pa

2. Aug 7, 2016

Greg Bernhardt

Thanks for the thread! This is an automated courtesy bump. Sorry you aren't generating responses at the moment. Do you have any further information, come to any new conclusions or is it possible to reword the post? The more details the better.