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REFLEAK: NIST Leak/Recharge Simulation Model for Refrigerant Blends, Version 5.0



Piotr A. Domanski, J S. Brown


As alternatives to refrigerants with a high global warming potential, blends of two or more refrigerants are being utilized as working fluids in heat-pumping, air-conditioning, and refrigeration systems, and organic Rankine cycles. Generally, these blends form zeotropes, which show temperature and composition changes during evaporation, condensation, or flashing process whether it be intended (i.e., through an expansion device) or unintended such as a leak from a container or system. For zeotropic blends, it may be important and necessary to predict the composition change for any of these leak conditions. REFLEAK simulates leak and recharge processes for refrigerant zeotropic blends. This Windows- based simulation model provides an easy-to-use package that allows estimation of composition changes of zeotropic blends in leak and recharge processes for either vapor or liquid leaks under isothermal or adiabatic conditions.
Natl Std. Ref. Data Series (NIST NSRDS) - 73
Report Number


air conditioning, refrigerant blends, refrigerant leak, zeotropic mixtures


Domanski, P. and Brown, J. (2016), REFLEAK: NIST Leak/Recharge Simulation Model for Refrigerant Blends, Version 5.0, Natl Std. Ref. Data Series (NIST NSRDS), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed July 12, 2024)


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Created December 14, 2016, Updated November 10, 2018