Mechanical MeasurementsFlow Measurements at Cryogenic TemperaturesTechnical Contact: Please contact the technical staff before shipping instruments or standards to the address listed below. Mailing Address:
Fees are subject to change without. back to top of page | back to index of mechanical measurements Special Tests of Cryogenic Liquid Flow (18800S)Measurement services are provided for cryogenic liquid flow. A dynamic weighing system is used to measure totalized mass flow and, with liquid density provided by the NIST Standard Reference Database 12: Thermophysical Properties of Pure Fluids, volumetric flow. Mass flow measurements are performed using liquid nitrogen at flow rates of 1 kg/s to 10 kg/s, over a pressure range of 0.4 MPa to 0.76 MPa, and a temperature range of 80 K to 90 K. The relative expanded uncertainty within this flow range, is 0.17%. For volumetric flow rate measurement, the uncertainty in fluid density must also be included. The relative expanded uncertainty for volumetric flow rate is 0.53%. Lower flow rates may be possible, but the uncertainty at these flows is undetermined.
back to top of page | back to index of mechanical measurements References–Flow Measurements at Cryogenic TemperaturesUncertainty Analysis of the NIST Nitrogen Flow Facility, J. L. Scott and M. A. Lewis, Natl. Inst. Stand. Technol. Tech. Note 1364 (Apr. 1994). Progress Report on Cryogenic Flow-metering at the National Bureau of Standards, J. A. Brennan, J. F. LaBreque, and C. H. Kneebone, Proc. 1st Biennial Symp. Instrumentation in the Cryogenic Industry, Houston, TX, Oct. 11–14, 1976, 1, 621, Instr. Soc. of America, Pittsburgh, PA (1976). NBS-CGA Cryogenic Flow Measurement Program, J. A. Brennan, R. W. Stokes, C. H. Kneebone, and D. B. Mann (Proc. ISA Intl. Instrument. Automation Conf. and Exhibit, New York, NY, Oct. 28–31, 1974), Paper in Adv. In Instrument. 29, 612.1 (Instr. Soc. Of America, Pittsburgh, PA, 1974). Cryogenic Flow Research Facility Provisional Accuracy Statement, J. W. Dean, J. A. Brennan, D. B. Mann, and C. H. Kneebone, Natl. Bur. Stand. (U.S.), Tech. Note 606 (July 1971). back to top of page | back to index of mechanical measurements Program questions: Calibrations Phone: 301-975-2200, Fax: 301-975-2950 NIST, |
