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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

temperature distribution graphs

Understanding Flow Meters

Ongoing
Critical flow venturis (CFVs) are widely used for gas flows of 1 L/min or more, if a significant pressure drop is acceptable. Theoretical discharge coefficient ( Cd): A calculated value of the discharge coefficient allows 0.3% uncertainty from a CFV from a low uncertainty throat diameter measurement
Transient flow facility for vehicle refueling

Transient Flow Facility

Completed
Impact Provide metrological tools and standards supporting the fair trade of hydrogen gas as a vehicle fuel of the future. Objectives Design, construct, and utilize a facility that mimics retail hydrogen fueling station conditions to quantify uncertainties of flow measurement standards and

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

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