Template for Exam Responses Note: Not all steps will be applicable to all problems. 1: State brie...
Eight (8) kilogram of saturated vapor of refrigerant R-134a is contained in a closed frictionless piston-cylinder device at a pressure of 200 kPa. Heat is then transferred to the refrigerant. At the end of the process, the refrigerant has a temperature of 70 °C. Determine the amount of heat that is transferred during the process. Also, show the process on a T-v diagram with respect to the saturated liquid and vapor lines. (35 points).
Problem I: Not applicable for 2017 Problem II: In an R-134a vapor-compression home heat pump, R-134A enters the compressor (75% isentropic efficiency) as a saturated vapor at 200 kPa and leaves at 800 kPa. The refrigerant goes through a constant pressure condenser and leaves as a saturated liquid. The refrigerant then goes through an adiabatic expansion valve enters the evaporator as a liquid-vapor mixture. The mass flow rate of refrigerant is 0.1 kg/s. and Cod A. Write the equation for...
Homework 2 Problem 1: A piston-cylinder device initially contains 0.35-kg steam at 3.5 MPa, superheated by 7.4 C. Now the stream loses heat to the surroundings and the piston moves down, hitting a set of stops at which point the cylinder contains saturated liquid water. The cooling continues until the cylinder contains water at 200C. Determine (a) the final pressure and the quality (if mixture), (b) the boundary work, (c) the amount of heat transfer when the piston first hits...
MEN215 Exam 1 S.. x ton... MEN215 Final Fall 57.5% 1 /3 Problem 1: 30 points Saturated water vapor at 180 "C is contained in a piston cylinder arrangement that has an initial volume of 0.025 m2. Heat is transferred and the steam expands in a polytropic process with n 1 until it reaches a pressure of 200 kPa. a) Find the amount of heat transferred in kl. b) Show the process path on a P-v diagram. MEN215 Exam 1...
Detailed answer please Problem 3 Consider a container divided by a partition into two chambers. The first chamber contains 15 kg of water at 350°C, 1.2 MPa. The other chamber contains 19 kg of water at 105 °C with 60 percent of the mass is in the liquid phase. The partition is now removed and the water in both chambers are allowed to mix until the system reaches a thermal equilibrium of 120°C. Determine: (a) The final pressure in the...
2. A piston-cylinder device maintain a constant pressure of 800 kPa while containing 20 kg of saturated water vapor. The system is heated with a resistance heater for 10 min at a current of 8 A at the standard wall voltage of 120 V. In that time, 3.2 kJ of heat is lost through the walls. What is the temperature at the heated state? 3 5-18E Hydrogen is contained in a piston-cylinder device at 14.7 psia and 15 ft. At...
Please solve all the problems, show all work and please do not copy from the others. Problem 1 A 3 HP heat pump operates between 0°F and 100°F. The maximum theoretical amount of Problem 2 An ideal vapor compression refrigeration cycle with R-134a as the working fluid operates between the pressure limits of 120 kPa and 1000 kPa. The mass fraction of the refrigerant that is in the liquid phase at the inlet of the evaporator is Problem 3 An...
Professor Modyn owns another piston-cylinder device, which initially (State 1) contains 0.236 m3 of saturated water vapor at 400.0 kPa. Heat is now slowly transferred to the steam until the volume doubles. Consider the expansion a two step process. First, constant volume heating occurs until the pressure reaches 500.0 kPa (State 2). Finally, a constant pressure expansion occurs resulting in the doubling of the initial volume (State 3) Note: The IUPAC sign convention for work is used. Work into the...
A gas contained in a piston cylinder assembly undergoes a process from state 1 to state 2 defined by the following relationship and given properties. Determine the heat transfer in kilojoules (k) to the system. Note: Carry five decimal places in all your calculations. p"V1.26 = constant E1 533.7 kj P1 348.2 kPa V1 2 m3 E2 511.7 kj P2 171.2 kPa Selected Answer: [None Given] Correct Answer: 343.00 ± 5%
Problem 1 A piston-cylinder system contains a paddle stirrer (a paddle with blades that can stir the contents of the cylinder). The cylinder contains a gas that is initially at 150 kPa and occupies a volume of 0.196 m3 . The piston is unrestrained and has a cross-sectional area of 0.196 m2 . 20 kJ of electrical energy is supplied to the paddle stirrer, resulting in the piston moving up by 0.2 m. During this process, 5.27 kJ of heat...