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Thermophysical Properties Division Overview


The Thermophysical Properties Division provides the best available measurements, theory, computations, and data evaluation for the thermophysical property information required to enable development of standards, enhance productivity, facilitate trade, ensure scientific and technological progress, and improve the quality of life.


The Thermophysical Properties Division (TPD) was formed at the beginning of 2008 by a reorganization which separated the old Physical and Chemical Properties Division into two entities with distinct focuses and each housed on one of the two main campuses of NIST. The TPD is a Division of the Material Measurement Laboratory located on the Boulder campus.

The Thermophysical Properties Division strives to be the foremost and best source of high quality thermophysical property information. This vision is driven by the ubiquitous importance of this information to commerce, industry, manufacturing, and national policy objectives. The Division meets its challenges through an integrated program of experimental measurement, data collection and evaluation, development of theoretically based models, and simulation of model systems. Among the outputs of the Division are computerized standard reference databases which synthesize thermophysical property information in forms which are conveniently used by our stakeholders.

The vast majority of commodity exchanges in chemicals, energy related fluids, and materials are based on physical and chemical properties. In some cases, national and international standards for these properties are needed, such as the AGA-8 equation of state for the properties of natural gas, ASME-IAPWS Properties of Water and Steam, ISO-Standard Equations for refrigerants. Generally these standards are presented in the form of high accuracy equations of state which allow determination of a wide range of thermodynamic properties. Additionally, performance criteria of working fluids, feedstock, chemicals, and cryogenic systems are inextricably linked to thermophysical properties, e.g. density, viscosity, boiling point, phase behavior, heat capacity, stability, etc. Engineering design, optimal operation, and innovation for engines, chemical manufacturing, power generation, heating and air conditioning, distillation, etc. depends critically on knowledge of these properties. Reliable properties data are critical to competitive advantage, sustainability, and innovation. Finally, we note that widespread reliance of industry on properties information, success in setting and achieving national energy, environmental, and security goals often requires an extensive and trustworthy properties information-base.

To meet the broad spectrum of needs, only briefly sketched above, the Division’s work is structured along four synergistic themes:

  • Develop and maintain the measurement capabilities, standard materials and reference data needed to underpin a national system of thermophysical property measurements;
  • Develop large-scale, readily accessible data resources providing trustworthy property information meeting high priority needs for a broad range of industries and national agendas;
  • Develop empirical and fundamental predictive capabilities to enable reliable estimation of property values when experimental data are unavailable;
  • Research experimental techniques and address key data-gaps in support of specific, high priority industrial and national initiatives.

These themes allow effective response to customer needs and are consistent with the Division’s operating strategy to maintain a highly synergistic research program that includes an appropriate balance of measurement, theory, and predictive models. The combination of the Division’s world class expertise and unrivaled resources in measurement, archiving, and provision of high-quality property data is complemented by its forefront research to develop reliable and highly adaptable methods for estimating property data in cases where measurements are unavailable or extremely difficult and/or costly to obtain.

Core Expertise

The expertise in the Division is broadly distributed within the fields of thermophysical properties and processes, emphasizing (1) data infrastructure and access; (2) predictive theory and models; and (3) experimental tools and measurements. More specifically, the Division maintains competence in data evaluation and dissemination; property models for industrial use; measurement of thermophysical properties; cryogenic technologies; separation technologies; fuel properties; and properties for environmental chemistry.

Key Interactions with Customers

Division outputs are routinely used in a variety of industrial, governmental, and academic settings. For instance, through a collaboration with Aspen Technology, evaluated data from the NIST Thermodynamic Data Engine are available to some 60,000 chemical plants world-wide. A consortium of chemical and related companies provides direct input to the data collection and evaluation programs of the Thermodynamic Research Center Group. The NIST REFPROP database was purchased by some 1200 customers in 2008, and all cryogenic flow meters in the U.S. are tied to the Division’s calibration and testing services. The Division houses the editorial offices of the International Journal of Thermophysics (and provides an editor of the Journal of Physical and Chemical Reference Data) and organizes the triennial Symposium on Thermophysical Properties to maintain connections.

Sponsored research in the Division also provides direct links to key customers: work with DOD (primarily the Air Force) is important to our fuels program; DHS funds some of our work on properties and data for explosives; DARPA works with the Division in its micro-cryocooler project; DOE is engaged in our properties work related to advanced power generation and in gas hydrates data.

Future Directions and Plans

The National challenges related to energy security and monitoring/mitigating anthropogenic climate (or other environmental) changes are reflected in the Division’s plans. The Division recently held workshops on property needs for biofuels and aerospace fuels: alternative fuels and feedstocks will command an increased emphasis in the future.

An image of a pyramid with experiment at the base. Theory is on top of experiment. Models is on top of theory. Data is on top of models.
Credit;  Image NIST

General Information:
303-497-3220 Telephone
303-497-5044 Facsimile

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Mailcode 838.00
Boulder, CO 80305-3337