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Metrology

Flow metrology & rheology

News and Updates

schematic of sound-wave transmitter and receiver

Sounding Out a New Way to Measure Gas Flow

Researchers at NIST have developed a new — and sound — way to accurately measure the rate at which gas flows in and out of a vessel. The technique, which uses

Projects and Programs

The NIST Chemistry Webbook

Ongoing
Intended Impact It is part of NIST's mission to distribute Standard Reference Data to scientists, engineers, educators, and the general public. The NIST Chemistry WebBook is intended to help fulfill NIST's mission by distributing such data over the Internet. Objective Develop a web site
MGI-Logo

Modeling Dispersion Rheology for Non-Spherical Particles

Completed
The goal of this MGI project is to establish an interactive database, generated by sophisticated modeling, such as dissipative particle dynamics and smooth particle hydrodynamics, to compute the rheological properties of polymer composites, where interaction among inclusions, inclusion particle

Precursor Material Qualification

Completed
To develop, utilize, and analyze methods of characterizing the precursor materials in additive manufacturing in both virgin and recycled states with the goal of advancing measurement science to benefit the AM community. The components of principal interest will include the rheological, size
water flow standard

Temperature Sensitivity of Liquid Flow Meters

Ongoing
The Fluid Metrology Group is using NIST’s 15 kg/s Liquid Flow Standard (LFS) [ 1] (Fig. 1) and data from the NIST cryogenic flow facility (decommissioned in 2020) [ 2] to better understand how coriolis meters are affected by the liquid and environment temperatures. The NIST water flow standard is a

Publications

Tools and Instruments

transient gas flow instruments

Transient Gas Flow Facility

A compressor is used to pressurize up to twenty-five 40 L gas cylinders to 35 MPa. The cylinders can then be used as a source of rapidly changing gas flow by
gas flow standards instrument

Gas Flow Standards

NIST uses pressure, volume, temperature, and time ( PVTt) standards to calibrate gas flow meters. PVTt flow standards generate selected, steady gas flows
wind tunnel instrument

Wind Tunnel

NIST’s wind tunnel can produce air speeds between 0.15 m/s and 40 m/s. The air speed reference is a Laser Doppler Anemometer (LDA) with an uncertainty of 2.5 %

Awards