A survey of experimental heat transfer data for nucleate pool boiling of liquid metals and a new correlation

The heat transfer and free convective motion, in inclined air layers heated from below, for angles of incidence 0 [les ] ϕ [les ] 30°, and Rayleigh numbers 100 < Ra cos ϕ < 10000, are studied experimentally. Results of both heat-transfer measurements and flow-visualization studies are reported. The purpose of the study was to investigate the fact, first noted by Hollands et al. (1976), that the experimental heat-transfer data, for ϕ > 20°, is not a function of the product Ra cos ϕ only, as expected from theoretical consideration. This discrepancy between theory and experiment is here attributed to a hypothesized secondary transition in the convective motion, due primarily to perturbation velocities in the upslope direction. This secondary transition appears to be the same as that predicted theoretically by Clever & Busse (1977); qualitative agreement with their theory is observed.

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Using Artificial Neural Networks to Develop a Predictive Method From Complex Experimental Heat Transfer Data

10.1115/imece2001/htd-24285 ◽

2001 ◽

Author(s):

Matthew D. Kelleher ◽

Thomas J. Cronley ◽

K. T. Yang ◽

Mihir Sen

Keyword(s):

Heat Transfer ◽

Neural Networks ◽

Artificial Neural Networks ◽

Complex Situation ◽

Transfer Data ◽

Predictive Algorithm ◽

Experimental Heat ◽

Predictive Method ◽

Experimental Heat Transfer ◽

Artificial Neural

Abstract Artificial neural networks are employed to develop a predictive algorithm using experimental heat transfer data for a complex situation. The data of Marto and Anderson has used to illustrate the process. This data is from a series of experiments investigating the boiling heat transfer from a vertical bank of tubes in refrigerant 114 with variable amounts of oil present. Both finned and unfinned tubes were investigated. The network was trained with a partial set of the available data. The prediction obtained using the trained network was then compared to the remaining experimental data. The artificial neural network provided an excellent predictive method.

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Model Wall and Recovery Temperature Effects on Experimental Heat-Transfer Data Analysis

AIAA Journal ◽

10.2514/3.49448 ◽

1974 ◽

Vol 12 (9) ◽

pp. 1169-1170 ◽

Cited By ~ 4

Author(s):

D. A. THROCKMORTON ◽

D. R. STONE

Keyword(s):

Heat Transfer ◽

Data Analysis ◽

Temperature Effects ◽

Transfer Data ◽

Experimental Heat ◽

Experimental Heat Transfer ◽

Recovery Temperature

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Condensation Heat Transfer Inside Multi-Port Minichannels

ASME 2nd International Conference on Microchannels and Minichannels ◽

10.1115/icmm2004-2390 ◽

2004 ◽

Cited By ~ 8

Author(s):

A. Cavallini ◽

D. Del Col ◽

L. Doretti ◽

M. Matkovic ◽

L. Rossetto ◽

...

Keyword(s):

Heat Transfer ◽

Experimental Research ◽

Air Conditioning ◽

Transfer Coefficients ◽

Air Conditioners ◽

Transfer Data ◽

Heat Transfer Coefficients ◽

Experimental Heat ◽

Experimental Heat Transfer ◽

Residential Air Conditioning

In this paper the experimental heat transfer coefficients measured during condensation of R134a and R410A inside multiport minichannels are presented. The need for experimental research on condensation inside multiport minichannels comes from the wide use of those channels in automotive air-conditioners. The perspective for the adoption of similar channels in the residential air conditioning applications also calls for experimental research on new high pressure refrigerants, such as R410A. Heat transfer data are compared against models to show the accuracy of the models in the prediction of heat transfer coefficients inside minichannels.

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Heat Transfer to the Highly Accelerated Turbulent Boundary Layer With and Without Mass Addition

Journal of Heat Transfer ◽

10.1115/1.3449701 ◽

1970 ◽

Vol 92 (3) ◽

pp. 499-505 ◽

Cited By ~ 21

Author(s):

W. M. Kays ◽

R. J. Moffat ◽

W. H. Thielbahr

Keyword(s):

Heat Transfer ◽

Boundary Layer ◽

Turbulent Boundary Layers ◽

Stanton Number ◽

Temperature Profiles ◽

Transfer Data ◽

Experimental Heat ◽

Prediction Scheme ◽

Experimental Heat Transfer ◽

Impermeable Wall

Experimental heat transfer data are presented for a series of asymptotic accelerated turbulent boundary layers for the case of an impermeable wall, and several cases of blowing, and suction. The data are presented as Stanton number versus enthalpy thickness Reynolds number. As noted by previous investigators, acceleration causes a depression in Stanton number when the wall is impermeable. Suction increases this effect, while blowing suppresses it. The combination of mild acceleration and strong blowing results in Stanton numbers which lie above the correlation for the same blowing but no acceleration. Velocity and temperature profiles are presented, from which it is possible to deduce explanations for the observed behavior of the Stanton number. A prediction scheme is proposed which is demonstrated to quite adequately reproduce the Stanton number results, using correlations derived from the profiles.

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Evaporative Heat Transfer in Microtubes With Diameters From 244 μm to 792 μm

Heat Transfer: Volume 2 ◽

10.1115/ht2005-72708 ◽

2005 ◽

Author(s):

Yun Wook Hwang ◽

Min Soo Kim

Keyword(s):

Heat Transfer ◽

Nucleate Boiling ◽

Transfer Coefficients ◽

Average Deviation ◽

Heat Transfer Coefficients ◽

Experimental Heat ◽

New Correlation ◽

Experimental Heat Transfer ◽

Flow Heat ◽

Evaporative Heat Transfer

The characteristics of the evaporative heat transfer in microtubes were investigated with three circular tubes with inner diameters of 244, 430, and 792 μm, respectively. The interrelation between the heat flux and the mass flux about the heat transfer coefficients was expressed by the boiling number, which was considered to be a very important parameter to predict the trend of the heat transfer coefficients in microtubes versus the quality. A new correlation for the evaporative heat transfer coefficients in microtubes was developed by considering the following factors; the laminar flow heat transfer coefficient of liquid-phase flow, the enhancement factor of the convective heat transfer, and the nucleate boiling correction factor. The correlation developed in this study predicts the experimental heat transfer coefficients within an absolute average deviation of 8.4%.

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