A piston-cylinder initially contains 10 kg of saturated liquid water at a pressure of 1000 kPa...

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A piston-cylinder initially contains 10 kg of saturated liquid water at a pressure of 1000 kPa (State 1). Then, during an isobaric process, heat is transferred to the water. At the final state, the water has a specific internal energy of 2793.7 kJ/kg (State 2). Remember that water is NOT an ideal gas so you should NOT be using the ideal gas equation. Use your tables to find properties. a) Sketch a schematic of this process. Identify your control mass and list the given properties at State 1 and State 2. (Similar to Homework 2 schematic) b) What is the quality, temperature, specific volume, and specific internal energy at State 1? c) What is the pressure at State 2? d) What are the temperature and specific volume at State 2? e) Calculate the boundary work for the process in units of kJ (Answer: about 20,000 kJ). Based on the sign of your answer, is the work in or out of the system? f) Calculate the change in internal energy (AU = U₂ - U₁) for the process in units of kJ. Remember that your table provides specific internal energy in units of kJ/kg so you need to multiply u by the mass of the system to get U. g) Using the 1 Law of Thermodynamics and your answers from e) and f), calculate the total heat transfer for the process in units of kJ. (Answer: between 22,000-23,000 kJ) h) In the analysis above, did you need to assume that the process was quasi-equilibrium? If so, which step required this assumption? A piston-cylinder initially contains 10 kg of saturated liquid water at a pressure of 1000 kPa (State 1). Then, during an isobaric process, heat is transferred to the water. At the final state, the water has a specific internal energy of 2793.7 kJ/kg (State 2). Remember that water is NOT an ideal gas so you should NOT be using the ideal gas equation. Use your tables to find properties. a) Sketch a schematic of this process. Identify your control mass and list the given properties at State 1 and State 2. (Similar to Homework 2 schematic) b) What is the quality, temperature, specific volume, and specific internal energy at State 1? c) What is the pressure at State 2? d) What are the temperature and specific volume at State 2? e) Calculate the boundary work for the process in units of kJ (Answer: about 20,000 kJ). Based on the sign of your answer, is the work in or out of the system? f) Calculate the change in internal energy (AU = U₂ - U₁) for the process in units of kJ. Remember that your table provides specific internal energy in units of kJ/kg so you need to multiply u by the mass of the system to get U. g) Using the 1 Law of Thermodynamics and your answers from e) and f), calculate the total heat transfer for the process in units of kJ. (Answer: between 22,000-23,000 kJ) h) In the analysis above, did you need to assume that the process was quasi-equilibrium? If so, which step required this assumption?

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Problem Isobaric Process of Saturated Liquid Water a Schematic and Properties Control Mass 10 kg of saturated liquid water State 1 Pressure P1 1000 kP... View the full answer