Fundamento
Refrigerating effect
The valve is modelled as isenthalpic, so h₄=h₃.
\(q_L=h_1-h_4\)
ThermoLab · Chapter 11
Refrigeration cycles
Plots the R-134a cycle on P-h and estimates COP, power and refrigerant flow rate.
Motor listo
Engineering results
NOT RUNDetailed calculation reportEquations · substitution · verification
Run the calculation to generate the report.
Engineering directory
13 linked modules on a single calculation base
Open any tool without losing your chosen unit system. Each page works on its own and keeps its navigation, report and export.
01
Appendices A-1 to A-28Universal property interpolator
→02Chapters 1 and 2Pressure, temperature and general energy balance
→03Chapter 3Pure substances and equations of state
→04Chapter 4Energy integrals for closed systems
→05Chapter 5Control volumes and the first law
→06Chapters 6 and 7Second law, Carnot and entropy
→07Chapter 8Exergy, destruction and second-law efficiency
→08Chapter 9Gas power cycles
→09Chapter 10Rankine steam power cycles
→10Chapter 11Refrigeration cycles
→11Chapters 12 and 13Gas mixtures and psychrometrics
→12Chapters 14 and 15Combustion and adiabatic flame temperature
→13Chapters 16 and 17Chemical equilibrium and compressible flow
→Engineering framework
Theory, equations and conditions of use
The cycle moves heat from a low temperature to a higher one. The P-h diagram makes evaporation, compression, condensation and throttling visible.
Fundamento
Compressor work
Isentropic efficiency corrects the ideal enthalpy rise.
\(w_c=h_2-h_1=(h_{2s}-h_1)/\eta_c\)
Fundamento
Coefficient of performance
COP relates the heat removed to the work supplied.
\(COP_R=q_L/w_c\)
Base documentalÇengel & Boles, 7th edition · SI appendices A-1 to A-28
USCS conversionA-1E to A-27E, via exact factors from the SI base
AlcancePreliminary design, teaching and independent verification
Engineering FAQ
Preguntas frecuentes
What effect does subcooling have?+
It increases the refrigerating effect by lowering h₃ and h₄.
Why superheat?+
It protects the compressor from liquid, although it can increase its work.
Does the valve produce work?+
Not in this model; it reduces pressure at approximately constant enthalpy.