thermodynamics

Question

A piston cylinder contains 1 kg of liquid water at 20oC and 300 kPa. There is a linear spring mounted on the piston such that when the water is heated the pressure reaches 3 MPa with a volume of 0.1 m3. Find the final temperature and the heat transfer in the process.

Answer 1

At constant volume

m₁ = m₂ = m

State 1 compressed liquid, take saturated liquid at same temperature.

according table B.1.1 V₁ = V_f(20)

 = 0.001002 m³/kg

State 2

V₂ = V₂/m = 0.1/2 = 0.05 m³/kg

P = 3000 K pa

Two phase T₂ = 233.9°c