B301 HYBRID GAS BEARING WITH WATER EVAPORATION FROM ULTRA-FINE POROUS MEDIUM

Corns, fruits, and vegetables are usually used as porous medium in drying process. But in fact, it must be considered as the cortex effect on mass transfer because the mass transfer of cortex is very difficult than inner medium. Based on the theory of heat and mass transfer, a coupled model for the porous medium vacuum drying process with cortex effect is constructed. The model is implemented and solved using COMSOL software. The water evaporation rate is determined using a nonequilibrium method with the rate constant parameterKrthat has been studied. The effects of different vapor pressures (1000, 5000, and 9000 Pa), initial moisture contents (0.3, 0.4, and 0.5 water saturation), drying temperatures (323, 333, and 343 K), and intrinsic permeability for cortex part (10−13, 10−14, 10−15 m2) on vacuum drying process were studied. The results facilitate a better understanding of the porous medium vacuum drying process that nearer to the reality.

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Stability of finite perturbations of the phase transition interface for one problem of water evaporation in a porous medium

Applied Mathematics and Computation ◽

10.1016/j.amc.2020.125208 ◽

2020 ◽

Vol 378 ◽

pp. 125208

Author(s):

Vladimir A. Shargatov ◽

Sergey V. Gorkunov ◽

Andrej T. Il’ichev

Keyword(s):

Phase Transition ◽

Porous Medium ◽

Water Evaporation ◽

Phase Transition Interface ◽

Transition Interface

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ANALYSES OF FREE CONVECTION FLOW OF AN INCLINED PLATE EMBEDDED IN A DOUBLE LAYER POROUS MEDIUM

Transactions of the Canadian Society for Mechanical Engineering ◽

10.1139/tcsme-2015-0019 ◽

2015 ◽

Vol 39 (2) ◽

pp. 269-279

Author(s):

Nabil Ibrahim Beithou

Keyword(s):

Heat Transfer ◽

Porous Medium ◽

Double Layer ◽

Water Desalination ◽

Water Evaporation ◽

Condensation Process ◽

Convection Flow ◽

Permeability Ratio ◽

Inclined Plate ◽

Constant Wall Temperature

Porous media offer wide practical applications, such as the use of the porous medium in solar water desalination systems to enhance water evaporation or condensation. Water condensation represents half of the desalination process. This study presents a simulation for the condensation process with double porous layers. This problem is simulated as the natural convection from an inclined plate embedded in a double layer porous medium; the plate was subjected to a constant wall temperature with variable layers thickness, permeability ratio and different plate angles. The effects of these parameters on the temperature distribution and total heat transfer were investigated. It has been found that the heat transfer rate increases with increasing the permeability ratio. Also increasing the layers thickness ratio in low permeability ratios, or keeping the layers ratio as minimum in the high permeability ratios are favorite. The inclination angle affects negatively the rate of heat transfer due to the buoyancy effect.

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Dynamics and stability of moving fronts of water evaporation in a porous medium

International Journal of Heat and Mass Transfer ◽

10.1016/j.ijheatmasstransfer.2014.12.027 ◽

2015 ◽

Vol 83 ◽

pp. 552-561 ◽

Cited By ~ 17

Author(s):

Vladimir A. Shargatov ◽

Andrej T. Il’ichev ◽

George G. Tsypkin

Keyword(s):

Porous Medium ◽

Water Evaporation

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Nonequilibrium Thermal Dynamic Modeling of Porous Medium Vacuum Drying Process

Mathematical Problems in Engineering ◽

10.1155/2012/347598 ◽

2012 ◽

Vol 2012 ◽

pp. 1-22 ◽

Cited By ~ 5

Author(s):

Zhijun Zhang ◽

Ninghua Kong

Keyword(s):

Mass Transfer ◽

Porous Medium ◽

Heat And Mass Transfer ◽

Water Saturation ◽

Coupled Model ◽

Water Evaporation ◽

Vacuum Drying ◽

Vapor Pressures ◽

Drying Process ◽

Medium Vacuum

Porous medium vacuum drying is a complicated heat and mass transfer process. Based on the theory of heat and mass transfer, a coupled model for the porous medium vacuum drying process is constructed. The model is implemented and solved using COMSOL software. The water evaporation rate is determined using a nonequilibrium method with the rate constant parameterKr. Krvalues of 1, 10, 1000, and 10000 are simulated. The effects of vapor pressures of 1000, 5000, and 9000 Pa; initial moistures of 0.6, 0.5, and 0.4 water saturation; heat temperatures of 323, 333, and 343 K; and intrinsic permeability of 10−13, 10−14, and 10−15 m2are studied. The results facilitate a better understanding of the porous medium vacuum drying process.

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