A piston-cylinder device that containing 20 kg of water initially has a volume of 0.65 m3 at 255oC.
The piston-cylinder device is then connected to a heat exchanger in a side-by-side configuration, which allows the heat transfer to the water at a rate of 33.71 kW until a final state of 400oC while the pressure remains constant as initial pressure. Inside the piston-cylinder device, a shaft work of 13.86 kW is continuously provided to improve mixing of water. To hasten the heating process,nan inlet stream of water at 1300oC and 1 MPa may be introduced at a mass flow rate of 4.3 kg/s
through the valve if the valve is allowed to be open. (Hint: there is one more work here.)

(a) Determine the initial phase and properties (pressure, internal energy, and enthalpy) of the water inside the piston-cylinder.
(4 Marks)

(b) Determine the final phase and properties (internal energy and enthalpy) of the water inside the piston-cylinder.
(3 Marks)

(c) Determine the phase and properties (internal energy and enthalpy) of the water in the inlet stream.
(3 Marks)

(d) Determine the duration of heat transfer process if the valve is fully closed.
(4 Marks)

(e) Determine the duration of heat transfer process if the valve is fully opened.
(6 Marks)

Answer rating: 100% (QA)

a The water inside the pistoncylinder is initially in a liquid state at 255oC and 065 m3 The pressur... View the full answer