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CYCLE_D: NIST Vapor Compression Cycle Design Program, Version 6.0; User's Guide



Piotr A. Domanski, J S. Brown, Eric W. Lemmon


The CYCLE_D package simulates vapor compression refrigeration cycles that use pure refrigerants or blends of refrigerants. The model can simulate a basic subcritical or transcritical refrigeration cycle, both with or without a liquid-line/suction-line heat exchanger. In addition, the model can simulate a subcritical two-stage economizer cycle, a subcritical three- stage economizer cycle, and a subcritical two-stage compression cycle with intercooling. Calculations are based on refrigerant properties as represented in the NIST Reference Fluid Thermodynamic and Transport Properties Program – REFPROP, Version 10.0 [1]. Simulation results are presented in terms of coefficient of performance (COP), volumetric capacity, thermodynamic parameters, and thermodynamic charts.
Natl Std. Ref. Data Series (NIST NSRDS) - 49-2018
Report Number


air conditioning, coefficient of performance, refrigeration, vapor compression


Domanski, P. , Brown, J. and Lemmon, E. (2018), CYCLE_D: NIST Vapor Compression Cycle Design Program, Version 6.0; User's Guide, Natl Std. Ref. Data Series (NIST NSRDS), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed June 16, 2024)


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Created November 19, 2018