Correlation of Heat and Mass Transfer Data for High Schmidt and Reynolds Numbers

1966 ◽  
Vol 5 (3) ◽  
pp. 370-379 ◽  
Author(s):  
D. W. Hubbard ◽  
E. N. Lightfoot
Keyword(s):  
Mass Transfer ◽  
Heat And Mass Transfer ◽  
Reynolds Numbers ◽  
Transfer Data

Effect of an Inert Gas on Heat and Mass Transfer in a Vertical Channel With Falling Films

1997 ◽  
Vol 119 (1) ◽  
pp. 24-30 ◽  
Author(s):  
Wei Chen ◽  
G. C. Vliet
Keyword(s):  
Mass Transfer ◽  
Heat And Mass Transfer ◽  
Film Flow ◽  
Vertical Channel ◽  
Reynolds Numbers ◽  
Momentum Equation ◽  
Limited Data ◽  
Low Reynolds Numbers ◽  
Noncondensable Gases ◽  
Energy Equations

The effect of inert (noncondensable) gases on the heat and mass transfer (absorption) for channel flow of water vapor in conjunction with falling aqueous LiBr films is investigated. The hydrodynamic flow of the gas in the channel is approximated as fully developed. This is a “fair” assumption because of the low Reynolds numbers resulting from the low prevailing absorber pressures. The film flow is also assumed to be hydrodynamically developed. This greatly simplifies the problem, as the momentum equation need not be considered. Otherwise the continuity, species, and thermal energy equations govern the problem. Numerical results for a nominal case are presented for the velocity, temperature, and species distributions in the gas and liquid phase regions, and for the interface absorption rate. The effects of varying several parameters (including inerts concentration) on the above variables are also presented. Comparisons are also made with limited data in the literature.

scholarly journals Momentum, heat, and mass transfer analogy for vertical hydraulic transport of inert particles

2014 ◽  
Vol 68 (1) ◽  
pp. 15-25
Author(s):  
Darko Jacimovski ◽  
Radmila Garic-Grulovic ◽  
Zeljko Grbavcic ◽  
Mihal Djuris ◽  
Nevenka Boskovic-Vragolovic
Keyword(s):  
Mass Transfer ◽  
Heat And Mass Transfer ◽  
Single Phase ◽  
Reynolds Numbers ◽  
Particle Flow ◽  
Phase Flow ◽  
Vertical Flow ◽  
Hydraulic Transport ◽  
Single Phase Flow ◽  
Transfer Coefficients

Wall-to-bed momentum, heat and mass transfer in vertical liquid-solids flow, as well as in single phase flow, were studied. The aim of this investigation was to establish the analogy among those phenomena. Also, effect of particles concentration on momentum, heat and mass transfer was studied. The experiments in hydraulic transport were performed in a 25.4 mm I.D. cooper tube equipped with a steam jacket, using spherical glass particles of 1.94 mm in diameter and water as a transport fluid. The segment of the transport tube used for mass transfer measurements was inside coated with benzoic acid. In the hydraulic transport two characteristic flow regimes were observed: turbulent and parallel particle flow regime. The transition between two characteristic regimes (?*=0), occurs at a critical voidage ??0.85. The vertical two-phase flow was considered as the pseudofluid, and modified mixture-wall friction coefficient (fw) and modified mixture Reynolds number (Rem) were introduced for explanation of this system. Experimental data show that the wall-to-bed momentum, heat and mass transfer coefficients, in vertical flow of pseudofluid, for the turbulent regime are significantly higher than in parallel regime. Wall-to-bed, mass and heat transfer coefficients in hydraulic transport of particles were much higher then in single-phase flow for lower Reynolds numbers (Re<15000), while for high Reynolds numbers (Re>15000), there was not significant difference. The experimental data for wall-to-bed momentum, heat and mass transfer in vertical flow of pseudofluid in parallel particle flow regime, show existing analogy among these three phenomena.

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