U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Metrology

Flow metrology & rheology

Projects/Programs

Displaying 1 - 16 of 16
The NIST Acoustic Thermometer

Acoustic Techniques in Fluid Metrology

Ongoing
In collaboration with NIST's Chemical Sciences Division, we use photoacoustic resonators for continuous monitoring of the CO2 concentration in ambient air from a tall building rooftop; (see Fig. 2) [ 1] for measuring the optical properties of particles (e.g. soot) in air that affect the energy
shaded quasi sphere

Atomic Standard for Pressure

Ongoing
Atomic physicists have calculated the pressure p( n, T) of helium gas as a function of the gas's temperature T and its refractive index at microwave frequencies, n. Near room temperature and 4 MPa, the fractional uncertainties from the calculations, the impurities in helium, state-of-art
Optofluidic device

Dynamic Nanoflow Metrology

Ongoing
Ultra-precise and dynamic flow measurements are needed for high-throughput biological studies and for dynamic control of chemical delivery systems in medical and biotechnology applications. In addition, existing analytical methods, such as analytical high-performance liquid chromatography (HPLC) and
microfluidic chip

Evaluating Measurement Quality of Microfluidic Cell-based Assays

Completed
Impact and Customers Our work establishes metrics for measurement quality and reproducibility for cell-based assays within microfluidic devices. Many novel microfluidic devices are being created that permit new measurements or enable new biological functions to be tested; however, characterizations
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

Material Qualification

Ongoing
Objective To develop, utilize, and analyze methods of characterizing the precursor materials in additive manufacturing in both virgin and recycled states with the goal of advancing measurement science to benefit the AM community. The components of principal interest will include the rheological
MGI-Logo

Modeling Dispersion Rheology for Non-Spherical Particles

Completed
The goal of this MGI project is to establish an interactive database, generated by sophisticated modeling, such as dissipative particle dynamics and smooth particle hydrodynamics, to compute the rheological properties of polymer composites, where interaction among inclusions, inclusion particle

The NIST Chemistry Webbook

Ongoing
Intended Impact It is part of NIST's mission to distribute Standard Reference Data to scientists, engineers, educators, and the general public. The NIST Chemistry WebBook is intended to help fulfill NIST's mission by distributing such data over the Internet. Objective Develop a web site
Optofluidic chip

Optofluidic Cytometry

Ongoing
Flow cytometers are commercial instruments that provide rapid multiparameter measurements of single cells, which makes them indispensable in basic research and clinical studies of diseases and drug therapies. Measurements of cellular attributes can include indicators of cell size and shape and well

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

Precursor Material Qualification

Completed
To develop, utilize, and analyze methods of characterizing the precursor materials in additive manufacturing in both virgin and recycled states with the goal of advancing measurement science to benefit the AM community. The components of principal interest will include the rheological, size

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
NIST researchers measuring a flow profile

Smoke Stack Flow Measurement

Ongoing
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
water flow standard

Temperature Sensitivity of Liquid Flow Meters

Ongoing
The Fluid Metrology Group is using NIST’s 15 kg/s Liquid Flow Standard (LFS) [ 1] (Fig. 1) and data from the NIST cryogenic flow facility (decommissioned in 2020) [ 2] to better understand how coriolis meters are affected by the liquid and environment temperatures. The NIST water flow standard is a
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
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