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Determine the isentropic efficency of a water pump?

7.63Determine the isentropic efficency of a water pump when water enters as a saturated liquid at 96.5 kPa and exits at 5 MPa and 106 degrees C.Thanks

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For the best answers, search on this site https://shorturl.im/ayhr9 1] INefficiency is associated with an increase in entropy, so the term 'isentropic efficiency' bothers me 2] Find the temp corresponding to a saturation pressure of 96.5 kPa [hint: something less than 100C]. 3] Look at the entropies in and out
Isentropic Efficiency
the only way a water pump can damage anything is if it locks up or quits working and the engine overheats and stops running. If your car has overheated enough and blew all the water out of the endgine and the head gasket went bad there may be water in your oil it would look milky like it had a milkshake in the oil. If your oil is ok and the coolant is not blowing out the tailpipe in big white clouds obscuring the cars behind you the engine may be ok as long as it has not blown steam for the last 20 minutes out the radiato Coolant may leak from the bottom of the water pump too if the water pump is bad. If the engine starts up and runds good in the morning and does not blow a bunch of steam at you it may be ok for awhile yet.r.
Well!!!!!!!! Isentroipc Efficiency of a pump = Isentropic Work / Actual Work At state 1, Enthalpy of Saturated Liquid h1 = 413.357 kJ/kg Entopy s1 = 1.29154 kJ/kg-K At state 2, Enthalpy of Liquid at state 2 = 448.042 kJ/kg Now, to find the ideal Enthaply , Enthalpy at 5 M Pa at entropy of 1.29154 kJ/kg-K h2s = 418.462 kJ/kg Thus, Isentropic Work Done I = h2s - h1 = 418.462 - 413.357 = 5.105 kJ/kg Actual Work Done A = h2- h1 = 448.042 - 413.357 = 34.685 kJ/kg Hence, Isentropic Efficiency = I/A = 5.105/34.685 = 14.72%

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