- #1

Xengine

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## Homework Statement

http://imgur.com/ktfgCAL

flow rate: 0.057 m^3/s

cross sectional area of all pipes: 1.864*10^-2 m²

frictional losses inlet pipe: 1.83m

frictional losses outlet pipe: 3.66m

density: 1000 kg/m^3

g= 9.81 N/kg

Asked:

pressure at inlet

pressure at outlet

necessary pumping power

## Homework Equations

Bernouilli: http://imgur.com/EEptkNX where h_A is the energy added by the pump and h_r and h_l are the losses

pumping power= q*rho*g*h

## The Attempt at a Solution

first of all, i am not sure what location they actually mean exactly by pump inlet and outlet (is it in the tank or really at the pump?)

inlet: I assumed p1 to be 0, v1=v2 and z1=0 and z2=3.05m which results in a p2 of 47.87kPa (i assumed h_A to be equal to 0, not sure if this is correct)

outlet: using the previous value as p1 now, assuming v1=v2 and z1=0 and z2=12.2m i found a p2 of 107.71 kPa

power: 0.057*1000*9.81*15.25 = 8.53kW

Apparentely, all my answers seem to be wrong. I'm fairly sure that I am making a critical mistake for the pressure calculations, but I really don't understand what could be wrong in my power calculation.

Thanks in advance :)

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