Consider the piston and cylinder arrangement indicated in the image below, in wh

Question

Consider the piston and cylinder arrangement indicated in the image below, in which a frictionless piston with a cross-sectional area of 0.06 m2 rests on stops on the cylinder walls such that the contained volume is 0.03 m3. The mass of the piston is such that 300 kPa pressure is required to raise the piston against the atmospheric pressure. When the piston has moved to a point where the contained volume is 0.075 m3, the piston encounters a linear spring that required 360 kN to deflect it 1 m. Initially the cylinder contains 4 kg of saturated (two-phase) water at 35oC. The final pressure is 7 MPa.

Q: Determine the the work done during the process and the final state of the H2O.

Explanation / Answer

area = 0.06 m2
initially V1 =.03 m3 or length X_1 = .03/.06= .5m

now as per the qts, p_2 - p_atm = A.Wt

   (300-101.325) KPa = Wt./.06

     198.675x103 = Wt./.06 wt= 1192.05 N

   m = 1192.05/9.81 = 121.51 Kg

SPRING CONSTANT:

if F=360 kN = 1m

K=360KN/m

Now for V2 = .075 m3 , length X_2 = .075/.06 =1.25m

distance of piston to spring = X_2 - X_1 = 1.25-.5 = .75m

Now P_1 = 0.5624 MPa @ 35 c

now at P_2 = 7 Mpa saturation temp (from steam table ) = 90 c

Q = M. C_p . T = 4x4186x(90-35)= 920.92 KJ

also

(as time is ending shortly pls do the furthur calculation yourself. if time limit increases i shall do it again

I hope i provided a bit of help)

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