Simultaneous heat and mass transfer during evaporation from a film of liquid into the turbulent gas

1982 ◽  
Vol 47 (3) ◽  
pp. 766-775 ◽  
Author(s):  
Václav Kolář ◽  
Jan Červenka
Keyword(s):  
Experimental Data ◽  
Mass Transfer ◽  
Liquid Film ◽  
Heat And Mass Transfer ◽  
Driving Forces ◽  
Proper Definition ◽  
Definition Of ◽  
Simultaneous Heat ◽  
Theory And Experiment

The paper presents results obtained by processing a series of published experimental data on heat and mass transfer during evaporation of pure liquids from the free board of a liquid film into the turbulent gas phone. The data has been processed on the basis of the earlier theory of mechanism of heat and mass transfer. In spite of the fact that this process exhibits a strong Stefan's flow, the results indicate that with a proper definition of the driving forces the agreement between theory and experiment is very good.

The Correlation of Simultaneous Heat and Mass Transfer Experimental Data for Aqueous Lithium Bromide Vertical Falling Film Absorption

2000 ◽  
Vol 123 (1) ◽  
pp. 30-42 ◽  
Author(s):  
William A. Miller ◽  
Majid Keyhani
Keyword(s):  
Experimental Data ◽  
Mass Transfer ◽  
Heat And Mass Transfer ◽  
Lithium Bromide ◽  
Falling Film ◽  
Bulk Concentration ◽  
Design Data ◽  
Flux Approximation ◽  
Aqueous Lithium Bromide ◽  
Simultaneous Heat

A study of simultaneous heat and mass transfer was conducted on a vertical falling film absorber to better understand the mechanisms driving the heat and mass transfer processes. Thermographic phosphors were successfully used to measure the temperature profile along the length of the absorber test tube. These measures of the local variations in temperature enabled calculation of the bulk concentration along the length of the absorber. The bulk concentration varied linearly, which infers that the concentration gradient in the direction of flow is approximately constant. The implication is that the mass flux and therefore the absorber load can be solved for using a constant flux approximation. Design data and correlations are sparse in the open literature. Some experimental data are available; however, all literature data to date have been derived at mass fractions of lithium bromide ranging from 0.30 to 0.60. Experiments were therefore conducted with no heat and mass transfer additive on an internally cooled smooth tube of 0.01905-m outside diameter and of 1.53-m length. The data, for testing at 0.62 and 0.64 mass fraction, were scaled and correlated into both Nu and Sh formulations. The average absolute error in the Nu correlation is about ±3.5% of the Nu number reduced from the experimental data. The Sh correlation is about ±5% of the reduced Sh data. Data from the open literature were reduced to the authors Nu and Sh formulations, and were within 5% of the correlations developed in the present study. The study therefore provides test data with no heat and mass transfer additive and correlations for the coupled heat- and mass-transfer process that are validated against the extensive experimental data.

Simultaneous heat and mass transfer with liquid film vacuum distillation

1973 ◽  
Vol 28 (8) ◽  
pp. 1519-1533 ◽  
Author(s):  
E.James Davis ◽  
Scott C. Hung ◽  
Charles S. Dunn
Keyword(s):  
Mass Transfer ◽  
Liquid Film ◽  
Heat And Mass Transfer ◽  
Vacuum Distillation ◽  
Simultaneous Heat
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