Heat Transfer in Bubble-Agitated Systems. A General Correlation

1976 ◽  
Vol 15 (1) ◽  
pp. 109-114 ◽  
Author(s):  
Wallace F. Hart
Keyword(s):  
Heat Transfer ◽  
General Correlation

Numerical Simulation of Gas/Solid Heat Transfer in Metallic Foams: A General Correlation for Different Porosities and Pore Sizes

2018 ◽  
Vol 127 (2) ◽  
pp. 481-506 ◽  
Author(s):  
Azade Jafarizade ◽  
Masoud Panjepour ◽  
Mahmood Meratian ◽  
Mohsen Davazdah Emami
Keyword(s):  
Heat Transfer ◽  
Numerical Simulation ◽  
Metallic Foams ◽  
General Correlation ◽  
Pore Sizes

Nucleate Boiling Performance of Refrigerants and Refrigerant-Oil Mixtures

1980 ◽  
Vol 102 (4) ◽  
pp. 701-705 ◽  
Author(s):  
S. Chongrungreong ◽  
H. J. Sauer
Keyword(s):  
Heat Transfer ◽  
Heat Transfer Coefficient ◽  
Transfer Coefficient ◽  
Significant Influence ◽  
Correlation Equation ◽  
Nucleate Boiling ◽  
Experimental Results ◽  
General Correlation ◽  
Oil Mixtures ◽  
The Heat Transfer Coefficient

Current and previous studies by the authors and others have shown shown that the carryover of oil in refrigeration systems can have a significant influence on the boiling performance in the evaporator of refrigeration systems. This investigation was conducted primarily to develop a general correlation equation for predicting the heat transfer coefficient for refrigerants and refrigerant-oil mixtures under pool boiling conditions. Experimental results were obtained to establish the validity of the correlation equation.

Elements of a General Correlation for Turbulent Heat Transfer

1996 ◽  
Vol 118 (2) ◽  
pp. 287-293 ◽  
Author(s):  
P. K. Maciejewski ◽  
A. M. Anderson
Keyword(s):  
Heat Transfer ◽  
Heat Flux ◽  
Temperature Rise ◽  
Adiabatic Temperature ◽  
Turbulent Velocity ◽  
Turbulent Heat Transfer ◽  
Turbulent Heat ◽  
Velocity Fluctuations ◽  
Adiabatic Temperature Rise ◽  
General Correlation

Typically, heat transfer researchers present results in the form of an empirically based relationship between a length-based Nusselt number, a length-based Reynolds number, and a fluid Prandtl number. This approach has resulted in a multitude of heat transfer correlations, each tied to a specific geometry type. Two recent studies have contributed key ideas that support the development of a more general correlation for turbulent heat transfer that is based on local parameters. Maciejewski and Moffat (1992a, b) found that wall heat transfer rates scale with streamwise turbulent velocity fluctuations and Anderson and Moffat (1992a, b) found that the adiabatic temperature rise is the driving potential for heat transfer. Using these two concepts and a novel approach to dimensional analysis, the present authors have formulated a general correlation for turbulent heat transfer. This correlation predicts wall heat flux as a function of the turbulent velocity fluctuations, the adiabatic temperature rise, and the fluid properties (density, specific heat, thermal conductivity, and viscosity). The correlation applies to both internal and external flows and is tested in air, water, and FC77. The correlation predicts local values of surface heat flux to within ± 12.0 percent at 95 percent confidence.

General Correlation for Heat Transfer to Gas–Liquid Flow in Vertical Channels

2018 ◽  
Vol 10 (6) ◽  
Author(s):  
Mirza M. Shah
Keyword(s):  
Heat Transfer ◽  
Liquid Mixtures ◽  
Absolute Deviation ◽  
General Correlation ◽  
New Correlation ◽  
Rectangular Channels ◽  
Wide Range ◽  
Data Points ◽  
Gas Liquid Flow ◽  
Dry Out

Abstract A general correlation is presented for heat transfer during flow of gas–liquid mixtures flowing in vertical channels prior to dry out. It has been verified with a wide range of data that include upward and downward flow in heated and cooled tubes, annuli, and rectangular channels. The data are from 19 studies and include 14 gas–liquid mixtures with a wide range of properties. The parameters include pressure 1–6.9 bar, temperature 16–115 °C, liquid Reynolds number from 2 to 127,231, superficial gas and liquid velocities up to 87 and 13 m/s, respectively, and ratio of superficial gas and liquid velocities 0.03–1630. The 1022 data points are predicted by the new correlation with mean absolute deviation (MAD) of 18.1%. Several other correlations were also compared to the same data and had MAD of 28.6–45.5%.

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