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CYCLE D: NIST Vapor Compression Cycle Design Program. Version 4.0. Users' Guide (NIST NSRDS 49)



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


The CYCLE_D package simulates vapor compression refrigeration cycles that use pure refrigerants or mixtures 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 withintercooling. CYCLE_D operates in a user-friendly Microsoft Windows environment that facilitates evaluating the performance of selected working fluids at different operating conditions. Calculations are based on refrigerant properties as represented in the NIST Reference Fluid Thermodynamic and Transport Properties Program - REFPROP, Version 8.0.
Natl Std. Ref. Data Series (NIST NSRDS) - 49
Report Number


refrigerants, refrigeration, compressing, installing, vapors, heat exchangers, computation


Brown, J. , Domanski, P. and Lemmon, E. (2009), CYCLE D: NIST Vapor Compression Cycle Design Program. Version 4.0. Users' Guide (NIST NSRDS 49), Natl Std. Ref. Data Series (NIST NSRDS), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed June 24, 2024)


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Created April 30, 2009, Updated October 12, 2021