Water is heated in a closed container with rigid walls that is a perfect cube (1 m x 1mx n). The initial volume of the water (liquid + vapor) is 1 m'. The initial temperature of he water is 100 °C and it has a quality of 0.3. It is heated until it reaches a final pressure of 700 kPa. a. Sketch the process on the P V diagram. b. What is the work done by the water during this heating process in kJ? c. What is the final temperature of the water? d. What is the heat required in order for this process to occur in kJ?

Solve these two maths showing the processes too in a well defined way.

(b) A frictionless piston-cylinder device as shown in Fig. Qlb contains water at 300 kPa and the water is heated at constant pressure from saturated liquid to saturated vapor. Then, the heating process is continued in an isobaric manner until its specific volume reaches the value of 0.7 m'/kg. Water Heat Figure Qlb i) What is the initial temperature of water in the cylinder? ii) What is the final temperature of water in the cylinder? iii) Calculate the total boundary work during the processes, kJ/kg. iv) Calculate the total amount of heat transferred during the processes, kJ/kg. v) Sketch both processes on a T – v diagram with respect to saturation lines.

A frictionless piston-cylinder device encloses 0.226 kg of saturated water-vapour mixture which is initially 10% by mass in liquid. The initial pressure is 1.035 MPa. The fluid is now heated until it all becomes saturated vapour. a. Find the work done during the process. Now, suppose that there is a stop in the cylinder that limits the piston to stop at the top when the volume is 0.0424 m'. b. Find the quality of the mixture when the piston just reached the stop, i.e. when the fluid volume is at 0.0424 m³.