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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

NIST researchers measuring a flow profile

Smoke Stack Flow Measurement

Completed
The Fluid Metrology Group is using its smoke stack simulator (See Fig. 1.) and field tests in operating smoke stacks to critically test conventional and improved ways of measuring the flow of stack gases. In the NIST stack simulator, the inlet cone and reference (upstream) section of the simulator
two-capillary viscometer

Gas properties for flow metering

Ongoing
NIST has two on-line databases that include accurate gas viscosity values: SEMIPROP - NIST Standard Reference Database 134 - for selected semiconductor process gases NIST Chemistry WebBook - for heat transfer fluids, components of air, components of natural gas [Note: as of February 2014, the NIST

Polymer Formulations

Completed
Bringing new and optimized formulated products to market requires measurements that will allow rapid assessment of the structure and properties of multicomponent mixtures over large parameter spaces. To this end, we are developing microfluidic "lab on a chip" technologies that enable researchers to

Qualification for AM Feedstocks, Machines and Processes

Completed
Objective - To develop, utilize, and analyze test methods and protocols for characterizing the feedstocks, machines, and processes in metal-based additive manufacturing to enable optimum usage and to reduce the cost and time needed for qualification. What is the Technical Idea? Qualification of AM

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