Nist Refprop Program

REFPROP is designed to run on any personal computer running the Microsoft® Windows® 98, 2000, XP, Vista, 7, 8, or similar operating system, both 32 bit and 64 bit. The program requires 20 MB of hard disk.

REFPROP is an acronym for REFerence fluid PROPerties. This program, developed by the National Institute of Standards and Technology (NIST), calculates the thermodynamic and transport properties of industrially important fluids and their mixtures. These properties can be displayed in Tables and Plots through the graphical user interface; they are also accessible through spreadsheets or user-written applications accessing the REFPROP dll.

REFPROP is based on the most accurate pure fluid and mixture models currently available. It implements three models for the thermodynamic properties of pure fluids: equations of state explicit in Helmholtz energy, the modified Benedict-Webb-Rubin equation of state, and an extended corresponding states (ECS) model. Mixture calculations employ a model that applies mixing rules to the Helmholtz energy of the mixture components; it uses a departure function to account for the departure from ideal mixing. Viscosity and thermal conductivity are modeled with either fluid-specific correlations, an ECS method, or in some cases the friction theory method.

It can be run as a stand-alone program with a graphical user interface on Windows machines. Tables as well as a variety of plots can be generated. You can also link to REFPROP via the REFPROP DLL from a variety of 3rd party software programs including Excel, MATLAB, Labview, etc. To install the program, right-click on the file below and select 'Save Target As.' Place this file in a temporary directory (which is not labeled Refprop), then run the executable to install mini-REFPROP to your harddrive. The executable for Version 10 of mini-Refprop was set to expire on Dec.

The property formulations and fluid data files were programmed by:

Refprop 10

Eric W. Lemmon, Ian H. Bell, Marcia L. Huber, and Mark O. McLinden
National Institute of Standards and Technology

REFPROP 10.0 is the culmination of several years of revisions and updates. Work never stops on the development of thermophysical properties and equations, but the last two years have been especially intense and fully dedicated to this release. Although there are only four authors of this work, we are very grateful to the many contributions of our NIST colleagues, including Gary Hardin, Allan Harvey, Chris Muzny, Vladimir Diky, Ala Bazyleva, and Janiel Reed who have provided support over the last several versions of REFPROP. Also of NIST are Adam Morey, Cindy McKneely, and Sherena Johnson who distribute the product for us to industry. A number of individuals from industry have contributed continuously over the last several years; we are indebted to them for their help, and we thank Tobias Loew, Nik Felbab, Nicolas James, Dan Williams, Jim Pollard, and Stuart Lawson.

2020Refprop 10 download

We acknowledge our many colleagues whose property models we have taken from the literature, and without which this database would be much reduced in scope. In particular, the Ruhr University in Bochum, Germany, has for many decades worked alongside us in the development of equations of state. The contributions of Wolfgang Wagner, Roland Span, and Monika Thol can easily be seen by browsing through the fluid information. We thank Marc Assael of Aristotle University of Thessaloniki (Greece) for his many contributions to the development of transport property formulations, and Ryo Akasaka of Kyushu Sangyo University for his contributions to the refrigerant equations of state. We also thank our colleagues within our division whose efforts have made possible the NIST/TRC SOURCE and TDE Databases, of which we have made extensive use for our data needs required to develop thermophysical property equations.

Program

Nist Refprop software, free download

Refprop

Although REFPROP is a program built on equations of state, its entire existence is built on a foundation of experimental data, some of which dates back to the late 1800s. Through experimental measurements, especially the highly accurate values of Wolfgang Wagner, Reiner Kleinrahm, Martin Trusler, Mark McLinden, Markus Richter, their students and colleagues, and many others, equations are built that are then used throughout industry world-wide. Many things that touch our lives have been influenced in one way or another by these measurements. Power generation alone affects all, and the properties from these equations influence the efficiency and design of that infrastructure. Likewise, heating, cooling, and transportation have all been influenced by the measurements and subsequent property equations. We are greatly indebted to the enormous work of so many scientists and engineers that continues unseen by most.

The development of this software package was supported by the NIST Applied Chemicals and Materials Division and the NIST Standard Reference Data Program. The development of the models and the measurement of the data on which REFPROP is based have been supported over a period of many years by numerous sponsors.

IMPORTANT: Please visit the REFPROP FAQ web site as your first resource when you encounter difficulties or have questions. Most email enquiries are answered by pointing to the FAQ. Using the FAQ will save valuable NIST resources that can be used to further develop REFPROP.

*Certain trade names and other commercial designations are used in this work for the purpose of clarity. In no case does such identification imply endorsement by the National Institute of Standards and Technology, nor does it imply that the products or services so identified are necessarily the best available for the purpose.

Background
Our company had an internal need to develop a RefProp C# interface that would enable calling the RefProp native FORTRAN methods from a Windows C# program. Discussions with the RefProp development team at NIST met with great enthusiasm and they helped guide us in the development of an open source project named IRefProp64, programs to quickly and easily call RefProp methods.

Overview
The IRefProp64 open source project consists of a .Net Assembly DLL (IRefProp64.dll) that can be added as a reference to Windows C# program to gain access to RefProp methods.
In addition, the project contains an example Windows C# program RefProp_CS_Examples.exe that contains three RefProp sample programs.

C# Source Code using IRefProp64 to Call RefProp Method SETPATHdll().

The following C# sample program with three tabs illustrates using the IRefProp64 C# interface to call RefProp methods.

Nist Refprop Program 2019

RefProp_CS_Examples.exe – Natural Gas (2 of 3)

Why the IRefProp64 C#/.Net Interface is Necessary
RefProp was initially written and is presently maintained in FORTRAN (since the 1970’s). It uses the Microsoft C-Runtime library to provide an interface for the FORTRAN routines to be called by native C/C++ code. However, C# (.Net) programs can not directly or easily interface to RefProp.

The diagram below shows the architecture of the C# interface to RefProp.

IRefProp64 – Block Diagram

The main difference between a C#/.Net program which runs in a “managed” environment, and an unmanaged native code program which runs in “unmanaged” environment (RefProp) is in how memory is allocated, released and formatted internally. Each environment requires the data such as (such as strings, integers and doubles) be converted and managed in their own internal format. The process of converting the internal memory from a managed to unmanaged (and vice versa) is known as “marshaling”. Fortunately, IRefProp64 handles the task of marshaling of data via the Microsoft COM interface. For a more technical discussion, please see the Microsoft MSDN article Interoperating with Unmanaged Code.

Mini Refprop Nist

Next Steps in Getting Started using the RefProp C# Interface…

  1. Download/run the sample RefProp_CS_Demo C# Windows programs binaries click here.
    (Visual Studio is not required)
  2. Watch our short quick start video C# Interface for REFPROP using IRefProp64.dll (below)
  3. Download the IRefProp64/RefProp_CS_Demo C# source code from NIST’s RefProp GitHub site and begin creating your C#/RefProp program

RefProp C# Tutorial Video
For a quick start tutorial on creating your own C#/.Net program that calls the native RefProp methods, please watch the following YouTube video:

Nist Refprop Program 2020

If You Need Help
Mill Creek Systems, Inc. provides software development services and can help with your software project needs with including a RefProp C# interface (and in other areas). Please contact us for a complimentary discussion of your needs.