Coupled heat and mass transfer modelling in convective drying of biomass at particle-level: Model validation with experimental data

2020 ◽  
Vol 149 ◽  
pp. 1290-1299 ◽  
Author(s):  
Gabriele A. Nagata ◽  
Thiago V. Costa ◽  
Maisa T.B. Perazzini ◽  
Hugo Perazzini
1982 ◽  
Vol 47 (3) ◽  
pp. 766-775 ◽  
Author(s):  
Václav Kolář ◽  
Jan Červenka

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.


Author(s):  
You-Rong Li ◽  
Dan-Ling Zeng

Based on non-equilibrium thermodynamic theory and combined with the conservation laws, a comprehensive theoretical model was established to describe heat and mass transfer during convective drying process, and numerical calculation was performed. The results show that: (a) the external convective heat and mass transfer may be treated as the conductive heat transfer with internal heat source and the molecular mass diffusion with internal mass source, respectively, and the ability of heat and mass transfer mainly depends on the strength of the heat source and mass source; the higher the temperature of the drying media, the lower the strength of the internal heat source, but the higher that of the internal mass sources; (b) the evaporation of internal water takes place inside the whole material, and the molecular mass diffusion of the internal vapor is in the direction of decreasing mass transfer potential, not along the decreasing partial pressure of vapor.


Author(s):  
M.R. Khosravi Nikou ◽  
M.R. Ehsani ◽  
M. Davazdah Emami

This paper describes the results of computational fluid dynamic modeling of hydrodynamics, heat and mass transfer simultaneously in Flexipac 1Y operated under a counter-current gas-liquid flow condition. The simulation was performed for a binary mixture of methanol-isopropanol distillation. The pressure drop, the height of equivalent to theoretical plate (HETP) and temperature distribution across the column were calculated and compared with experimental data. The mean absolute relative error (MARE) between CFD predictions and experimental data for the pressure drop, HETP and temperature profile are 20.7%, 12.9% and 2.8%, respectively.


2020 ◽  
Author(s):  
Eflita Yohana ◽  
Nazaruddin Sinaga ◽  
Haryo Pachusadewo ◽  
M. Irfan Nugraha ◽  
M. Endy Yulianto ◽  
...  

Author(s):  
Hongfang Gu ◽  
Qi Chen ◽  
Zhe Zhang ◽  
Haiyang Guo

The numerous studies on condensation flow patterns and heat transfer were focused on the horizontal inside single tube. A number of heat and mass transfer correlations are used for design of shellside condensers based on tubeside condensation flow regimes. Due to a complex geometry and measurement difficulty in a tube bundle, there are few publications reported on shellside condensation flow regime and heat transfer characteristics. To investigate the condensation flow patterns and heat and mass transfer mechanism at the different flow regimes, a horizontal shellside condenser was tested from a multipurpose condensation rig recently. The horizontal test bundle is made of 36 tubes with the staggered tube layout. The tube OD is 19 mm and the tube length is 1.0 m using stainless steel. Four visualization windows were placed on the front and back sides on the shell for photographing condensation flow patterns. Steam and steam/air mixture were used as the test fluids. The condensation flow patterns, condensate film thickness and droplets distribution were recorded using a high-speed digital camera at a wide range of condensation process conditions. The experimental data show that the condensation flow regime changes from the shear-controlled flow to gravity-controlled flow depending on the vapor and condensate loads, bundle location and the concentration of the non-condensable gas. These experimental data provide a fundamental approach for developing the heat and mass transfer correlateons at different shellside condensation patterns. This paper presents the experimental result on shellside condensation patterns associated with heat transfer characteristics.


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