A piston-cylinder device initially contains 2 kg of refrigerant-134a at 100 kPa and 20°C. Heat is now transferred to the refrigerant from a source at 150°C, and the piston, which is resting on a set of stops, starts moving when the pressure inside reaches 120 kPa. Heat transfer continues until the temperature reaches 80°C. Assume the surroundings to be at 25°C and 100 kPa. R-134a 100 kPa 20°C Q 150°C Problem 08.048.c - Exergy Destroyed by Piston Device with Refrigerant Determine the exergy destroyed. (You must provide an answer before moving on to the next part.) The exergy destroyed is [ kJ.

A piston-cylinder device initially contains 2 kg of refrigerant-134a at 100 kPa and 20°C. Heat is now transferred to the refrigerant from a source at 150°C, and the piston, which is resting on a set of stops, starts moving when the pressure inside reaches 120 kPa. Heat transfer continues until the temperature reaches 80°C. Assume the surroundings to be at 25°C and 100 kPa. R-134a 100 kPa 20°C Q 150°C Problem 08.048.c - Exergy Destroyed by Piston Device with Refrigerant Determine the exergy destroyed. (You must provide an answer before moving on to the next part.) The exergy destroyed is [ kJ.

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

See similar textbooks

Similar questions

A Piston-Cylinder system initially contains R-134a refrigerant at a temperature of 2.8 bar and 40°C and an initial volume of 0.1 m3. First, heat is transferred to the system by keeping the piston constant and this process is continued until the pressure is 3.2 bar. The process is then maintained by allowing the volume to change while the pressure is kept constant. At the end of this process, the temperature reaches 50°C. Assuming the state changes as if they are balanced,calculate;a) The mass of R-134a refrigerant in the system,b) The amount of heat transferred during the fixed volume process,c) The amount of heat transferred during constant pressure operation.d) Show the state changes on the P-v diagram.
One kg of superheated steam is at 400 kPa and 400°C. Heat is added to raise the temperature to 500°C. Find the amount of heat needed (kJ) if: (a) The volume of the steam is kept constant during the heating. (b) The steam is allowed to expand during the heating (e.g., in a piston/cylinder system) such that the pressure is constant. Hint: The steam is not an ideal gas under these conditions.
A frictionless piston-cylinder device initially contains 80 L of liquid saturated with refrigerant 134a. The piston has free movement, and its mass is such that it maintains a pressure of 500 kPa on the refrigerant. The refrigerant is then heated until its temperature rises to 70 ° C. Calculate the work done during this process.
A piston and cylinder arrangement contains saturated water vapor at 110°C. The vapor is compressed in a reversible, adiabatic process until the pressure is 1.6 MPa. What is the work done to or by the system in BTU if the mass of the vapor is 6.745 kg?
A frictionless piston cylinder device initially contains 200L of saturated liquidrefrigerated R134a. The piston is free to move, and its mass is such that it maintainsa pressure of 900 kPa on the refrigerant. The refrigerant is now heated until itstemperature rises to 70 oC. Calculate the work done in the process.
5-62 Refrigerant-134a is throttled from the saturated liquid state at 700 kPa to a pressure of 160 kPa. Determine the tem- perature drop during this process and the final specific vol- ume of the refrigerant. Answers: 42.3°C, 0.0345 m³/kg P₁ = 700 kPa sat. liquid R-134a P₂ = 160 kPa FIGURE P5-62
A 12-ft3 rigid tank contains refrigerant-134a at 30 psia and 55 percent quality. Heat is transferred now to the refrigerant from a source at 120°F until the pressure rises to 50 psia. Assuming the surroundings to be at 75°F, determine the amount of heat transfer between the source and the refrigerant.
Air in a closed-piston cylinder is initially at 100 kPa and 27°C. It is then compressed until the pressure reaches 2 MPa in a polytropic process with n = 1.3. Determine how much boundary work in kJ/kg must be supplied into the system to make this process possible. Round your answer to the nearest whole number.
A piston-cylinder device contains 50 kg of water at 250 kPa and 25°C. The cross-sectional area of the plunger is 0.1 m2. Heat is transferred to the water, causing some of it to evaporate and expand; When the volume reaches 0.2 m3, the piston hits a linear spring whose spring constant is 100 kN/m. More heat is transferred to the water until the plunger rises a further 20 cm. Determine a) the final pressure and temperature and b) the work done during this process. Also show the process on a P-V diagram.
A variable-load piston-cylinder device contains air (cp = 1.005 kJ/kgK; cv = 0.718 kJ/kgK) at 500 kPa and T=12 oC. A paddle wheelequipped within the system and turned by an external electric motor until 65 kJ/kg of work has been transferred to the air. During this process the gas volume is quadrupled while maintaining the temperature constant by transferring heat to the gas. Determine (a) the final pressure, (b) the amount of required heattransfer (c) Show this process on a P-v diagram. Do not use Table A-17 while solving this problem. YOUR ANSWER SHEET SHOULD INCLUDE THE SOLUTION AND THE TABLE BELOW (a) Pinal [kPa] = (b) q [kJ/kg]