A Method for Critical Heat Flux Prediction in Vertical Round Tubes with Axially Non-uniform Heat Flux Profile
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In this study a method to predict CHF (Critical heat flux) in vertical round tubes with axially non-uniform cosine heat flux distribution for water was examined. For this purpose a local condition hypothesis based CHF prediction correlation for uniform heat flux in vertical round tubes for water was developed from 9,366 CHF data points. The local correlation consisted of 4 local condition variables: the system pressure (P), tube diameter (D), mass flux of water (G), and 'true mass quality' of vapor (Xt). The CHF data points used were collected from 13 different published sources having the following operation ranges: 1.01 ≤ P (pressure) ≤ 206.79 bar, 9.92 ≤ G (mass flux) ≤ 18,619.39 kg/m2s, 0.00102 ≤ D (diameter) ≤ 0.04468 m, 0.0254 ≤ L (length) ≤ 4.966 m, 0.11 ≤ qc (CHF) ≤ 21.41 MW/m2, and –0.87 ≤ Xc (exit qualities) ≤ 1.58. The result of this work showed that a uniform CHF correlation can be easily extended to predict CHF in axially non-uniform heat flux heater. In addition, the location of the CHF in axially non-uniform tube can also be determined. The local uniform correlation predicted CHF in tubes with axially cosine heat flux profile within the root mean square error of 12.42% and average error of 1.06% for 297 CHF data points collected from 5 different published sources.
Abstract
In this study a method to predict CHF (Critical heat flux) in vertical round tubes with axially non-uniform cosine heat flux distribution for water was examined. For this purpose a local condition hypothesis based CHF prediction correlation for uniform heat flux in vertical round tubes for water was developed from 9,366 CHF data points. The local correlation consisted of 4 local condition variables: the system pressure (P), tube diameter (D), mass flux of water (G), and 'true mass quality' of vapor (Xt). The CHF data points used were collected from 13 different published sources having the following operation ranges: 1.01 ≤ P (pressure) ≤ 206.79 bar, 9.92 ≤ G (mass flux) ≤ 18,619.39 kg/m2s, 0.00102 ≤ D (diameter) ≤ 0.04468 m, 0.0254 ≤ L (length) ≤ 4.966 m, 0.11 ≤ qc (CHF) ≤ 21.41 MW/m2, and –0.87 ≤ Xc (exit qualities) ≤ 1.58. The result of this work showed that a uniform CHF correlation can be easily extended to predict CHF in axially non-uniform heat flux heater. In addition, the location of the CHF in axially non-uniform tube can also be determined. The local uniform correlation predicted CHF in tubes with axially cosine heat flux profile within the root mean square error of 12.42% and average error of 1.06% for 297 CHF data points collected from 5 different published sources.
참고문헌 (26)
- Burnout Data for Flow of Boiling Water in Vertical Round Ducts, Annuli, and Rod Clusters, "Becker, K.M", Aktiebolaget Atomenergie Report AE-, 177~ (1965)
- Round Tube Burnout Data for Flow Boiling of Water at Pressures between 30 and 200 bar, Royal Institute of Technology, "Becker,K.M.", Laboratory of Nuclear Engineering, ~, pp.KTH-NEL-14 (1971)
- Critical Heat Flux Data for Fully Developed Flow of Steam‐Water Mixtures in Round Vertical Tubes with Non Uniform Axial Power Distribution, "Bertoletti,S.", CISE, ~, pp.Report R-74. (1963)
- Second Experimental Study of Dryout in a Long Vertical Tube with a Cosine Heat Flux, "Casterline,J.E", Columbia University, ~, pp.Topical Report No. 5 TASK-XVI (1965)
- Burnout in Vertical Long Tubes with Uniform and Cosine Heater Using Water at 1000 psia, "Casterline,J.E.", Columbia University, ~, pp.Topical Report No. I, TASK-XVI (1964)
- Single Tube Tests (for) Critical Heat Flux Test Program, "Cheh,H.Y.", ~, pp.CU-HTRF-T8 (1992)
- Collier J.G., "Convective Boiling and Condensation, 3rd ed" (1994), Oxford University Press
- Deng,Z., "A New Correlation for Flow Boiling of Water in Subcooled and Quality Region", Proc. 8th Int. Topl. Mtg. Nuclear Reactor Thermal-Hydraulics, 2, pp.981~ (1997)
- Deng,Z., "Prediction of Critical Heat Flux for Flow Boiling in Subcooled and Saturated Regions", Ph.D., pp.1998
- Forced Convection Boiling Burnout for Water in Uniformly Heated Tubular Test Sections, "Griffel,J", Columbia University, ~, pp.NYO-187-7 (1965)
- Jafri,T., "Local and non-local correlations for Critical Heat Flux at Low and Medium Pressures", the ASME Heat Transfer Division, pp.229~238 (1996)
- Katto,Y., "An Improved Version of the Generalized Correlation of Critical Heat Flux for Forced Convection Boiling in Uniformly Heated Vertical Tubes", J. Heat Mass Transfer, 27(9), pp.1641~1648 (1984)
- Kim,H.C., "Critical Heat Flux of Water in Vertical Round Tubes at Low Pressure and Low Flow Conditions", Nuclear Engineering and Design, 199, pp.49~73 (2000)
- Kim,H.G., "Development of a Generalized Critical Heat Flux Correlation through the Alternating Conditional Expectation Algorithm", Nuclear Engineering and Design, 127, pp.300~316 (1997)
- An Experimental Investigation of Forced Convection Burnout in High Pressure Water, Part Ⅲ, "Lee,D.H.", Long Tubes with Uniform and Non‐uniform Axial Heating, ~, pp.AEEW-R355 (1965)
- An Experimental Investigation of Forced Convection Burnout in High Pressure Water, Part Ⅳ, "Lee,D.H.", Large Diameter Tubes at about 1600 PSI, ~, pp.AEEW-R479 (1966)
- An Experimental Investigation of Convection Burnout in High Pressure Water. Part I, "Lee,D.H.", Round Tubes with Uniform Heat Flux Distribution, ~, pp.AEEW-R213 (1963)
- Lowdermilk,W.H., "Investigation of Boiling Burnout and Flow Stability for Water Flowing in Tubes, NACA-TN-4382", ~ (1958)
- Mishima,K., "Boiling Burnout at Low Flow Rate and Low Pressure Conditions", Ph. D., pp.1984
- Shah,M.M., "Improved General Correlation for Critical Heat Flux during Upflow in Uniformly Heated Vertical Tubes", Heat and Fluid Flow, 8(4), pp.326~335 (1987)
- Saha,P., "Point of Net Vapor Generation and Vapor Void Fraction in Subcooled Boiling", the 5th International Heat Transfer Conference, pp.175~179 (1974)
- Shim,W.J., "Development and Analysis of a Uniform CHF Database", JIEC, 8(3), pp.268~275 (2002)
- Shim,W.J., "Prediction of CHF in Vertical Round Tubes with Uniform Heat Flux for Water", JIEC, 12(1), pp.127~133 (2006)
- The Influence of Axial Heat Flux Distribution on the Departure from Nucleate Boiling in a Water Cooled Tube, "Swenson,H.S.", ASME, ~, pp.62-WA-297 (1963)
- Boiling Water Heat Transfer Burnout in Uniformly Heated Round Tubes: A Compilation of World Data with Accurate Correlations, "Thompson,B.", United Kingdom Atomic Energy Authority, ~, pp.AEEW-R-356 (1964)
- Tong,L.S., "Boiling Heat Transfer and Two‐Phase Flow" (1965), John Wiley & Sons