FLOW PATTERN-RECOGNITION IN HEATED VERTICAL CHANNELS - STEADY AND TRANSIENT CONDITIONS

被引：9

作者：

CELATA, GP

CUMO, M

FARELLO, GE

MARIANI, A

SOLIMO, A

机构：

[1] ENEA CASACCIA ENE-IMPE-IPROT, Thermal Process Engineering Division Rome

[2] Energetics Department, University of Rome, Rome

来源：

EXPERIMENTAL THERMAL AND FLUID SCIENCE | 1991年 / 4卷 / 06期

关键词：

FLOW PATTERN; OPTICAL PROBES; PDF; MEASUREMENT TECHNIQUE; FREON-12; CRITICAL HEAT FLUX;

D O I：

10.1016/0894-1777(91)90081-2

中图分类号：

O414.1 [热力学];

学科分类号：

摘要：

Experimental work was carried out to determine the flow pattern map in vertical heated pipes under steady-state and transient conditions, using Freon 12 in forced convective flow as working fluid and optical probes for the measurements. Existing maps are based on adiabatic tests, steady-state conditions, and fluids different from Freon 12. Signals from optical probes (whose response is based on the variations in fluid refractive index) are analyzed in terms of local void fraction, using either the probability density function (PDF) or the ratio between the average and maximum values of the signal. From the analysis of the experimental measurements the definition of a map for annular and intermittent flow regimes was achieved. The map turned out to be in good agreement with the Weisman and Kang map developed in adiabatic, steady-state conditions. Qualitative results for the transient conditions are also presented.

引用

页码：737 / 746

页数：10

共 17 条

[1]

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[2]

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[3]

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[4]

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[5]

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[6]

Celata, Cumo, D'Annibale, Farello, Mariani, ANATRA—A Computer Code for Transient Critical Heat Flux Analysis with Refrigerant-12, Int. J. Heat Technol., 8, 3-4, pp. 1-29, (1990)

[7]

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[8]

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[9]

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[10]

Annunziato, Giradrdi, Two-Phase Flow Pattern Recognition in Straight Tubes, 19th Informal Meeting on Reactor Noise, (1989)

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