Considering now the real case, where the turbine and feed pump are not isentropic, and the feed pump electric motor and the electric generator are not 100% efficient: We have: Refrigerant: R134A Boiler working pressure: 1200kPa (absolute) Refrigerant temperature after boiling: 68.64 °C Amount of heat available from geothermal water: directly proportional to 5 degrees drop of geothermal water. Geothermal water specific heat capacity: 4.2 kJ/kg.K Boiler to turbine isentropic efficiency: 81.6% Boiler feed pump isentropic efficiency: 87.3% Condenser saturation pressure: 723kPa Electric Generator Efficiency: 83.33 Efficiency of electric motor driving boiler pump: 81.6% a) Calculate the actual specific enthalpy and actual specific entropy and the actual temperature of the refrigerant at the exit of the feed pump, and the exit of the turbine/expander; b) Sketch and label the ideal and actual process paths of the cycle on a T-s diagram, an h-s diagram and a P-v diagram.

Considering now the real case, where the turbine and feed pump are not isentropic, and the feed pump electric motor and the electric generator are not 100% efficient: We have: Refrigerant: R134A Boiler working pressure: 1200kPa (absolute) Refrigerant temperature after boiling: 68.64 °C Amount of heat available from geothermal water: directly proportional to 5 degrees drop of geothermal water. Geothermal water specific heat capacity: 4.2 kJ/kg.K Boiler to turbine isentropic efficiency: 81.6% Boiler feed pump isentropic efficiency: 87.3% Condenser saturation pressure: 723kPa Electric Generator Efficiency: 83.33 Efficiency of electric motor driving boiler pump: 81.6% a) Calculate the actual specific enthalpy and actual specific entropy and the actual temperature of the refrigerant at the exit of the feed pump, and the exit of the turbine/expander; b) Sketch and label the ideal and actual process paths of the cycle on a T-s diagram, an h-s diagram and a P-v diagram.

Refrigeration and Air Conditioning Technology (MindTap Course List)

8th Edition

ISBN:9781305578296

Author:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Publisher:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Chapter22: Condensers

Section: Chapter Questions

Problem 7RQ: When a standard-efficiency air-cooled condenser is used, the condensing refrigerant will normally be...

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