An Air Conditioner: Refrigerator or Heat Pump?

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SUMMARY

This discussion focuses on the thermodynamic principles of air conditioners, specifically comparing them to refrigerators. The scenario involves 7.00 kg of refrigerant with 54.0% in liquid form and 46.0% as vapor entering the evaporator. The refrigerant transitions to 95% vapor by the time it reaches the compressor. To calculate the heat absorbed (Q_c) during the evaporation process, the heat of vaporization is given as 1.50×105 J/kg. The key calculation involves determining the mass of the refrigerant that transforms from liquid to vapor and applying the heat of vaporization to find Q_c.

PREREQUISITES
  • Understanding of thermodynamics, specifically phase changes of refrigerants
  • Familiarity with the concept of heat of vaporization
  • Basic knowledge of mass flow rates in refrigeration cycles
  • Ability to perform unit conversions and calculations involving percentages
NEXT STEPS
  • Calculate the mass of liquid refrigerant converted to vapor using the given percentages
  • Apply the heat of vaporization formula to find the total heat absorbed (Q_c)
  • Research the properties of common refrigerants used in air conditioning systems
  • Explore the thermodynamic cycles of refrigeration and air conditioning systems
USEFUL FOR

This discussion is beneficial for students studying thermodynamics, HVAC technicians, and engineers involved in refrigeration system design and analysis.

Kalie
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Air conditioners operate on the same principle as refrigerators. Consider an air conditioner that has 7.00 kg of refrigerant flowing through its circuit each cycle. The refrigerant enters the evaporator coils in phase equilibrium, with 54.0% of its mass as liquid and the rest as vapor. It flows through the evaporator at a constant pressure and when it reaches the compressor 95% of its mass is vapor. In each cycle, how much heat Q_c is absorbed by the refrigerant while it is in the evaporator? The heat of vaporization of the refrigerant is 1.50×105 kg/J

All right I don't know what to do
I know I have to find the percentage of refrigerant transformed to vapor which is 49%
Now I have to calculate the heat needed to transform this amount of refrigerant to vapor. But I don't know how, I just need the absic equation please help.
 
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Find the mass of the liquid that gets converted to to vapor using the percentages. Check the units on the heat of vaporization. Did you type that correctly?
 

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