Can someone please solve the following problem showing every step clearly and th

Question

Can someone please solve the following problem showing every step clearly and the solutions so that it is easy for me to follow? I will award all of the points to the correct answer with the most thorough work. Thanks!!!

Water at 27 degree C (rho = 1000 kg/m3) is pumped adiabatically from 1 bar to 19.7 bar in a steady flow process. Find the minimum work magnitude (assuming delta KE 0). Repeat the minimum work calculation, but now for compressing air (ideal) instead of pumping water. Assume inlet temperature and inlet/exit pressures are the same as for the water. Use nearest table value in the air table. Repeat part b, but assume constant air properties evaluated at 300k

Explanation / Answer

Work done = change in enthalpy [no heat is given]

H=U+PV .. ?H= ?U + P?V + V?P

considering water to be an incompressible fluid, P?V=0 and ?U=0 since temp remains constant.

Rate of work done per mass of water= ?H/m = ?P/density = 18.7bar/1000kg/m3= 1.87 kJ/kg

For air, ?H/m = h1-h2 where h1 and h2 are the state enthalpies noted from the air table.

For adiabatic process, work done per unit mass= P1V1-P2V2/(1.4-1)*m= P1/.4*density1-P2/.4*density2

Where density at state 2 and 1 can be found out from the given table.

Density=(specific volume)^-1

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