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Material Measurement Laboratory /Applied Chemicals and Materials Division

Thermophysical Properties of Fluids Group

The Thermophysical Properties of Fluids Group performs experimental measurements and develops models and empirical correlations to describe and predict thermodynamic and transport properties for a variety of industrially relevant fluids and fluid mixtures including fuels, refrigerants, bulk chemicals and specialty chemicals.

The Thermophysical Properties of Fluids Group performs experimental, theoretical and simulation research on the thermodynamic and transport properties of fluids and fluid mixtures over wide ranges of temperature, pressure and composition; develops and maintains state-of-the-art apparatus to measure properties such as pressure-volume-temperature, phase equilibrium, heat capacity, speed of sound, enthalpy, viscosity, and thermal conductivity; develops models and empirical correlations to describe and predict thermophysical property surfaces; develops and certifies standard reference materials and measurement protocols for fluids; and provides comprehensive thermophysical property measurements, evaluated property data and computer databases for technically or industrially important fluid systems including common inorganics, industrial chemicals, refrigerants, hydrocarbons, aqueous systems, coal conversion products, heavy oils, and other fuels (including precursors, additives, and production/waste streams). Based on this research, the group develops publicly available software for the retrieval of comprehensive and evaluated Standard Reference Data, constituting recommended values, for the properties of technically important fluids and fluid mixtures.

News and Updates

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Projects and Programs

Cover of the ASME International Steam Tables for Industrial Use, Third Edition

Contributions to International Standards on the Properties of Water

Ongoing
Water is probably the most widely used industrial fluid and it is important to have internationally accepted standards for its properties. This information is crucial to the analysis and design of thermal power cycles, as well as for climate studies including the hydrosphere. (Here is a summary of
densimeter

Flow Metering and Properties for Semiconductor Process Gases

Ongoing
A type of flow meter called a mass flow controller (MFC) is used to regulate gas flow in order to produce the desired structures during chip fabrication. As semiconductor manufacturing advances, the requirements on MFC performance are increasingly strict: any process variation can reduce device
A collage of REFPROP screens

Reference Fluid Thermodynamic and Transport Properties Database (REFPROP)

Ongoing
REFPROP is a computer program, distributed through the Standard Reference Data program of NIST, that provides thermophysical properties of pure fluids and mixtures over a wide range of fluid conditions including liquid, gas, and supercritical phases. It contains critically evaluated mathematical
Color coded refrigerant bottles

Refrigerants and Working Fluids

Ongoing
We apply a wide range of experimental apparatus to the task of measuring the properties of working fluids. Many of these instruments are the same as those used in our work on standard reference fluids, and our data for working fluids approach the accuracy of the reference fluids. Thermodynamic

Publications

temo: teqp‐based model optimization

Author(s)
Ian Bell
The temo library is a set of building blocks that facilitate the automation of fitting models to experimental data for thermodynamic properties. The library is

Awards

Staff

Name Phone Number Email
Ian Bell
(303) 497-6970
 ian.bell [at] nist.gov (ian[dot]bell[at]nist[dot]gov)
Tara Fortin
(303) 497-3522
 tara.fortin [at] nist.gov (tara[dot]fortin[at]nist[dot]gov)
Allan H. Harvey
(303) 497-3555
 allan.harvey [at] nist.gov (allan[dot]harvey[at]nist[dot]gov)
Marcia L. Huber
(303) 497-5252
 marcia.huber [at] nist.gov (marcia[dot]huber[at]nist[dot]gov)
Eric W. Lemmon
(303) 497-7939
 eric.lemmon [at] nist.gov (eric[dot]lemmon[at]nist[dot]gov)
Michael Lewis
(303) 497-3458
 michael.lewis [at] nist.gov (michael[dot]lewis[at]nist[dot]gov)
Mark O. McLinden
(303) 497-3580
 mark.mclinden [at] nist.gov (mark[dot]mclinden[at]nist[dot]gov)
Stephanie L. Outcalt
(303) 497-5786
 stephanie.outcalt [at] nist.gov (stephanie[dot]outcalt[at]nist[dot]gov)
Richard A. Perkins
(303) 497-5499
 richard.perkins [at] nist.gov (richard[dot]perkins[at]nist[dot]gov)
Elizabeth Rasmussen (303) 497-7411 elizabeth.rasmussen [at] nist.gov (elizabeth[dot]rasmussen[at]nist[dot]gov)
Aaron Rowane (303) 497-5158 aaron.rowane [at] nist.gov (aaron[dot]rowane[at]nist[dot]gov)

Contacts

Group Leader