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NIST Standard Reference Database 73

REFLEAK: NIST Leak/Recharge Simulation Program for Refrigerant Blends

REFLEAK 6.0 Image

Version 6.0

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REFLEAK estimates composition changes of zeotropic mixtures in leak and recharge processes. The leak/recharge simulation program consists of three parts: 1) the pre-processing section for inputting required data, 2) the computation section which simulates leak/recharge processes, and 3) the post-processing section to display calculated results and to print or store data and graphs.

REFLEAK offers the following:

  • Choice of simulation mode between leak only and leak/recharge
  • Choice of process between isothermal (slow) and adiabatic (fast) leak conditions
  • Choice of vapor leak or liquid leak
  • Choice of 71 refrigerants
  • Choice of any mixture, up to 10 components, comprising the above refrigerants
  • Choice of 103 predefined refrigerant mixtures
  • Choice of specifying the initial temperature and initial volumetric quality of charge directly or through specifying the maximum liquid fill at a different fill temperature. The second option is consistent with the specification of the initial volumetric quality used in ANSI/ASHRAE Standard 34, "Designation and Safety Classification of Refrigerants".     
  • Choice of specifying the number of recharges, up to 10, and the % mass leaked after each.

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. A Help Menu and User’s Guide with simulation examples are included.

Compared to previous versions, this version 6.0 of REFLEAK is based on NIST Standard Reference Database 23 - NIST Reference Fluid Thermodynamic and Transport Properties Database: REFPROP Version 10.0, with updated representation of refrigerant thermophysical properties and extended list of refrigerants.

System Requirements: 

  • Personal computer capable of running Microsoft Windows 7, 8, 10 with Microsoft .NET Framework version 4.7.2 or later and Microsoft Visual C++ Runtime Library (for x86) version 14 or later, with a hard disk with 17 MB of available space.  The installation process will require additional 104 MB of space for Microsoft .NET Framework version 4.7.2 and Microsoft Visual C++ Runtime Library (for x86) version 14 if they are not installed already.
  • Screen resolution set to 1024 x 768 or higher to view images in their entirety. 

Please click here to view the PDF version of User’s Guide to see how this database works.

For more information, please contact:
Standard Reference Data, NIST:
100 Bureau Drive, Stop 6410
Gaithersburg, MD 20899-6410
Tel: 844-374-0183 (Toll Free)
data [at] (data[at]nist[dot]gov) (E-MAIL)

The scientific contact for this database is:
Mark O. McLinden
National Institute of Standards and Technology
Thermophysical Properties of Fluids Group 
325 Broadway, Mailstop 647.08
Boulder, CO 80305 USA
1-303-497-3580 markm [at] (markm[at]boulder[dot]nist[dot]gov)

Keywords: Chemical leak; fractionation; recharge; refrigerant; thermodynamic properties; zeotropic mixtures; NIST.

data [at] (Customer Support)

Created August 27, 2010, Updated June 13, 2024