State-of-the art dimensional metrology was used to measure the throat diameter and throat curvature of nine critical flow venturis (CFVs) with nominal throat diameters ranging from . The throat curvature was used in calculating the theoretical discharge coefficients, while the throat diameter was used in computing the experimental discharge coefficients. The nine CFVs were calibrated in dry air using two NIST primary flow standards with expanded uncertainties of 0.05% and 0.09%, respectively. The calibration data span a Reynolds number range from to , including laminar, transition, and turbulent flow regimes. By correcting for both the throat diameter and curvature, the agreement between predicted and measured discharge coefficients was less than 0.17% in the turbulent regime and less than 0.07% in the laminar regime.
1.
Wright
, J. D.
, 1998, “The Long Term Calibration Stability of Critical Flow Nozzles and Laminar Flowmeters
,” Proceedings of the 1998 NCSL Workshop and Symposium
, Albuquerque, NM
, NCSL
, pp. 443
–462
.2.
ISO 9300
: (E), 1990, “Measurement of Gas Flow by Means of Critical Flow Venturi Nozzles
,” Geneva, Switzerland.3.
Ishibashi
, M.
, Takamoto
, M.
, Watanabe
, N.
, Nakao
, Y.
, and Yokomizo
, T.
, 1994, “Precise Calibration of Critical Nozzles of Various Shapes at the Reynolds Number of 0.8–2.5×105
,” Proceedings of Flow Measurement
, Glasgow, UK
.4.
Ishibashi
, M.
, Morioka
, T.
, and Arnberg
, B. T.
, 2005, “Effect of Inlet Curvature on the Discharge Coefficients of Toroidal-Throat Critical-Flow Venturi Nozzles (Keynote Paper)
,” ASME Summer Meeting and Exhibition
, Houston, TX
, ASME Paper No. FEDSM2005-77470.5.
Ishibashi
, M.
, 2003, “Fluid Dynamics in Critical Nozzles Revealed by Measurements (Keynote Paper)
,” Fourth ASME/JSME Joint Fluids Engineering Conference
, Honolulu, HI
, ASME Paper No. FEDSM2005-45592.6.
Ishibashi
, M.
, 2002, “Super-Fine Structure in the Critical Flow-Rate of Critical Flow Venturi Nozzles
,” Joint US-European Fluids Engineering Conference
, Montreal, Canada
, ASME Paper No. FEDSM2002-31079.7.
Wright
, J. D.
, Johnson
, A. N.
, and Moldover
, M. M.
, 2003, “Design and Uncertainty Analysis for a PVTt Gas Flow Standard
,” J. Res. Natl. Inst. Stand. Technol.
1044-677X, 108
, pp. 21
–47
.8.
Wright
, J. D.
, Moldover
, M. R.
, Johnson
, A. N.
, and Mizuno
, A.
, 2003, “Volumetric Gas Flow Standard With Uncertainty of 0.02% to 0.05%
,” ASME J. Fluids Eng.
0098-2202, 125
(6
), pp. 1058
–1066
.9.
Johnson
, A. N.
, and Wright
, J. D.
, 2006, “Gas Flowmeter Calibrations With the 26m3 PVTt Standard
,” Journal of Research of the National Institute of Standards and Technology, NIST Special Publication 250-1046
.10.
Johnson
, A. N.
, Wright
, J. D.
, Moldover
, M. R.
, and Espina
, P. I.
, 2003, “Temperature Characterization in the Collection Tank of the NIST 26m3 PVTt Gas Flow Standard
,” Metrologia
0026-1394, 40
, pp. 211
–216
.11.
Stoup
, J. R.
, and Doiron
, T. D.
, 2001, “The Accuracy and Versatility of the NIST M48 Coordinate Measuring Machine
,” Proc. SPIE
0277-786X, 4401
, pp. 136
–146
.12.
Taylor
, B. N.
, and Kuyatt
, C. E.
, 1994, “Guidelines for Evaluating and Expressing the Uncertainty of NIST Measurement Results
,” NIST TN-1297.13.
ISO
, 1995, “Guide to the Expression of Uncertainty in Measurement
,” International Organization for Standardization (ISO)
, Geneva, Switzerland.14.
John
, J. E.
, 1984, Gas Dynamics
, 2nd ed., Allyn and Bacon
, Boston
.15.
Tang
, S.
, 1969, “Discharge Coefficients for Critical Flow Nozzles and Their Dependence on Reynolds Numbers
,” Ph.D. thesis, Princeton University, Princeton, NJ.16.
Geropp
, D.
, 1971, “Laminare Grenzschichten in Ebenen und Rotationssymmetrischen Lavalduesen
,” Deutsche Luft-Und Raumfart, Forschungsbericht, pp. 71
–90
.17.
Stratford
, B. S.
, 1964, “The Calculation of the Discharge Coefficient of Profiled Choked Nozzles and the Optimum Profile for Absolute Air Flow Measurement
,” J. R. Aeronaut. Soc.
0368-3931, 68
, pp. 237
–245
.18.
Hall
, I. M.
, 1962, “Transonic Flow in Two-Dimensional and Axially-Symmetric Nozzles
,” Q. J. Mech. Appl. Math.
0033-5614, 15
, pp. 487
–508
.19.
Kliegel
, J. R.
, and Levine
, J. N.
, 1969, “Transonic Flow in Small Throat Radius of Curvature Nozzles
,” AIAA J.
0001-1452, 7
, pp. 1375
–1378
.20.
Johnson
, R. C.
, 1964, “Calculations of Real-Gas Effects in Flow Through Critical Nozzles
,” ASME J. Basic Eng.
0021-9223, 86
, pp. 519
–526
.21.
Back
, L. H.
, and Cuffel
, R. F.
, 1971, “Flow Coefficients for Supersonic Nozzles With Comparatively Small Radius of Curvature Throats
,” J. Spacecraft
, 8
(2
), pp. 196
–198
.22.
Smith
, R. E.
, and Matz
, R. J.
, 1962, “A Theoretical Method of Determining Discharge Coefficients for Venturis Operating at Critical Flow Conditions
,” ASME J. Basic Eng.
0021-9223, 84
(4
), pp. 434
–446
.23.
Massier
, P. F.
, Back
, L. H.
, Noel
, M. B.
, and Saheli
, F.
, 1970, “Viscous Effects on the Flow Coefficient for a Supersonic Nozzle
,” AIAA Technical Note, pp. 605
–607
.24.
Ishibashi
, M.
, and Takamoto
, M.
, 1997, “Very Accurate Analytical Calculation of the Discharge Coeffcients of Critical Venturi Nozzles With Laminar Boundary Layer
,” Proceedings of the FLUCOME
, Hayama, Japan
, Sept. 14.25.
White
, F. M.
, 1991, Viscous Fluid Flow
, McGraw-Hill
, New York
.26.
Johnson
, A. N.
, Wright
, J. D.
, Nakao
, S.
, Merkle
, C. L.
, and Moldover
, M. R.
, 2000, “The Effect of Vibrational Relaxation on the Discharge Coefficient of Critical Flow Venturis
,” Flow Meas. Instrum.
0955-5986, 11
(4
), pp. 315
–327
.27.
Johnson
, A. N.
, 2000, “Numerical Characterization of the Discharge Coefficient in Critical Nozzles
,” Ph.D. thesis, Pennsylvania State University, University Park, PA.Copyright © 2008
by American Society of Mechanical Engineers
You do not currently have access to this content.
