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Metrology

Flow metrology & rheology

News and Updates

Projects and Programs

NIST researchers measuring a flow profile

Smoke Stack Flow Measurement

Presently used methods to measure CO2 and other emissions from smoke stacks have errors of 20 % or more depending on the level of swirl in the flow. The
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

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