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A Standard Choked Nozzle for Absolute Calibration of Air Flowmeters

Published online by Cambridge University Press:  04 July 2016

D. W. Sparkes
D. W. Sparkes*
Affiliation:
National Gas Turbine Establishment, Pyestock
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Summary

A choked nozzle installation suitable tor the absolute calibration of air flowmeters over a limited flow range is described. An entry package is prescribed to ensure that near ideal flow conditions are presented to the nozzle. This package should remove swirl and flow distortions from most entry flows.

Provided that the instructions given in this note are followed meticulously then the quoted discharge coefficients for the nozzle may be guaranteed to better than ±0-25% at Reynolds numbers greater than 106. The overall accuracy of flow calibrations are then dependent only on the accuracy with which the mean gas thermodynamic properties and condition of state at the nozzle entry can be determined.

Type
Technical Notes
Information
The Aeronautical Journal , Volume 72 , Issue 688 , April 1968 , pp. 335 - 338
Copyright
Copyright © Royal Aeronautical Society 1968 

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References

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