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REFLEAK: NIST Leak/Recharge Simulation Program for Refrigerant Mixtures Version 3.2



David Didion, Min S. Kim, Piotr A. Domanski


REFLEAK simulates leak and recharge processes for refrigerant zeotropic mixtures, and estimates composition changes for vapor and liquid under either isothermal or adiabatic leak conditions. Calculated vapor and liquid compositions are displayed in a graphic format. Additional tabular data includes temperature, pressure, volumetric quality, liquid specific volume and vapor specific volume for each 1% of mass leaked throughout the process. Output data can be saved and printed. Thermodynamic properties of refrigerant mixtures are calculated based upon the NIST Standard Reference Database 23 - NIST Reference Fluid Thermodynamic and Transport Properties Database: REFPROP, Version 8.0.
Natl Std. Ref. Data Series (NIST NSRDS) -


composition change, leak, recharge, refrigerant, zeotropic mixture


Didion, D. , Kim, M. and Domanski, P. (2009), REFLEAK: NIST Leak/Recharge Simulation Program for Refrigerant Mixtures Version 3.2, Natl Std. Ref. Data Series (NIST NSRDS), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed April 24, 2024)
Created October 15, 2009, Updated October 12, 2021