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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

Events

Projects and Programs

acoustic resonator

Acoustic Techniques in Fluid Metrology

Ongoing
We use acoustic techniques in gases to measure the thermodynamic temperature of a gas in a spherical or cylindrical cavity, the optical absorption in gases and aerosols (in collaboration with NIST’s Chemical Sciences Division) the quantity of gas in a large vessel or tank, and gas flow into/from a

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

Publications

Calibrating laser Doppler anemometers utilizing an optical chopper

Author(s)
Christopher Crowley, Iosif Isaakovich Shinder, Michael R. Moldover, Joey Boyd, James Filla, Aaron Johnson
Laser Doppler anemometers (LDAs) use scattered light to determine velocity components of a flowing fluid. The operating principal of LDAs is simple conceptually

Tools and Instruments

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 %
gas pipeline

Natural Gas Flow Calibration Service

Name(s) of Calibrations/SRMs/SRD/SRIs and any related programs: NIST Special Tests for Natural Gas Flow (18080S) Summary The Fluid Metrology Group (FMG)
gas flow standards thumbnail

Gas Flow Standards

Summary NIST's gas flow meter calibrations support a wide range of industries that require low-uncertainty, SI-traceable measurements. These industries include
15 kg/s liquid flow standard

Liquid Flow Standards

Summary The Fluid Metrology Group has a dynamic, gravimetric liquid flow standard spanning the flow range 0.2 L/s to 15 L/s with uncertainty less than 0.03 % at

Awards