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Metrology

Flow metrology & rheology

News and Updates

Projects and Programs

Diagram of NIST's Smoke Stack Simulator test bed

Smoke Stack Simulator

Today, inconsistencies between measured CO2 emissions and emissions calculated from coal consumption are on the order of 10% to 20%. The objective of this
two-capillary viscometer

Gas properties for flow metering

Flow meters that rely on measuring the pressure drop across a laminar flow element can be accurately calibrated using a benign surrogate gas (such as helium or

Precursor Material Qualification

The lack of repeatable process outcomes from additive manufacturing (AM) has been broadly acknowledged as an impediment to widespread implementation. While most

Publications

Faster, More Accurate, Stack-Flow Measurements

Author(s)
Aaron N. Johnson, Iosif I. Shinder, Bernard J. Filla, Joey T. Boyd, Rodney A. Bryant, Michael R. Moldover, Thomaa D. Martz, Matthew Gentry
Exhaust flows from coal-fired electricity-generating-plants are determined by measuring the flue gas velocity at prescribed points in the stack cross section

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 through
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