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Metrology

Flow metrology & rheology

News and Updates

Projects and Programs

AM Machine and Process Qualification

Ongoing
Machines and processes used to produce critical components for defense, aerospace, and medical applications must first be formally qualified. While
Optofluidic chip

Optofluidic Cytometry

Ongoing
This NIST-wide collaborative project aims to improve biotechnology and medical diagnostics by increasing the resolution and precision of measurements of cells
NIST researchers measuring a flow profile

Smoke Stack Flow Measurement

Ongoing
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

Ongoing
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

Publications

Gas Flow Standards and Their Uncertainty

Author(s)
John D. Wright, Aaron Johnson, Michael R. Moldover, Shin-ichi Nakao
We review diverse types of gas flow standards that are used to calibrate other gas flow meters. For each type of standard, we describe the principles of its

SerialTrack: ScalE and Rotation Invariant Augmented Lagrangian Particle Tracking

Author(s)
Jin Yang, Yue Yin, Alexander Landauer, Selda Buyukozturk, Jing Zhang, Luke Summey, Alexander McGhee, Matthew Fu, John Dabiri, Christian Franck
We present a new particle tracking algorithm to accurately resolve large deformation and rotational motion fields, which takes advantage of both local and

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