Consider a water pump that recieves liquid water at 15C and 100kPa, and delevers it to a same diameter short pipe having a nozzle with exit diameter of .01m to the atmosphere at 100 kPa. Neglect KE in pipes and assume constant internal energy u for water. Find exit velocity and mass flow rate if the pump draws 1kW of power.(adsbygoogle = window.adsbygoogle || []).push({});

I started with the energy equation but since the pressure and internal energy is the same, wont the he and hi also be the same? If I reduce I get

[tex]

\begin{array}{l}

\omega = - \frac{1}{2}V^2 \\

V = \sqrt { - 2\omega } \\

V = \sqrt {( - 2)( - 1kW)} \\

\end{array}

[/tex]

Which isn't giving me the right velocity of 29.43 m/s. I know it has to do with the exit area but its not comming to me, can anyone point me in the right direction? Thanks.

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# Homework Help: Pump and nozzle

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