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Orifice Meter Discharge Coefficient Database Available For PC Users

A new database with important information on the performance of orifice meters in measuring fluid flows is now available from the Standard Reference Data Program at the National Institute of Standards and Technology. The personal computer database will be helpful to the owners and operators of gas and oil pipelines, mechanical and petroleum engineers, industrial designers, researchers and others concerned with flow measurement.

NIST Standard Reference Database 45, GRI/NIST Orifice Meter Discharge Coefficient Database, Version 1.0, was developed under a grant from the Gas Research Institute. The data were compiled by scientists in the NIST Process Measurements Division, Boulder, Colo.

GRI sponsored research at NIST Gaithersburg and Boulder, and Southwest Research Institute, San Antonio, Texas. Cooperating laboratories included British Gas, United Kingdom; Colorado Engineering Experiment Station Inc.; Delft Hydraulics Laboratory and Gasunie, the Netherlands; and the National Engineering Laboratory, Scotland.

The database contains data for five working fluids: air, gas-oil, nitrogen gas, natural gas and water, in orifice meter line sizes of 50 millimeters to 600 millimeters. Other information includes meter tube size, surface roughness and pressure tap orientation.

In addition to information on fluids, there are data on installation conditions such as long upstream straight pipe, elbow, tees and reducers at varying positions. Information also is included for the performance of flow conditioners that may be inserted in piping configurations that are less than ideal. The conditioners include Sprenkle, Zanker, etoile or tube bundle.

Depending upon the option chosen, the search results can be displayed in either a tabular or graphical format. The user also can select metric units (SI) or conventional engineering values for tube diameter, orifice diameter, flow pressure, temperature, density and differential pressure. At the conclusion of a search, the user can display discharge coefficients against a pipe Reynolds number along with discharge coefficients predicted by the orifice meter equation. Information from the search also can be saved in an ASCII file for later use.

The GRI/NIST Orifice Meter Discharge Coefficient Database, Version 1.0, is available for $240. It is designed for any PC-DOS or MS-DOS computer using DOS 3.3 or greater and at least 8MB memory and a color monitor.

To order NIST Standard Reference Database 45, contact the Standard Reference Data Program, A320 Physics Building, NIST, Gaithersburg, Md. 20899-0001, (301) 975-2208, fax: (301) 926-0416, e-mail: SRDATA [at] (SRDATA[at]enh[dot]nist[dot]gov) (via Internet).

As a non-regulatory agency of the Commerce Department's Technology Administration, NIST promotes U.S. economic growth by working with industry to develop and apply technology, measurements and standards.

Released July 22, 1994, Updated June 2, 2021