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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

Projects and Programs

Refrigerants and Working Fluids

The conversion of primary energy (e.g. heat generated by the combustion of a fuel) into useful work most often involves a working fluid operating in a




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


Group Leader