Numerical Analysis of Thermal-Solutal Convection in Heterogeneous Porous Media

2005 ◽  
Vol 73 (1) ◽  
pp. 21-25 ◽  
Author(s):  
Charles-Guobing Jiang ◽  
M. Ziad Saghir ◽  
M. Kawaji
Keyword(s):  
Porous Media ◽  
Thermal Diffusion ◽  
Soret Effect ◽  
Heterogeneous Porous Media ◽  
Soret Coefficient ◽  
Solutal Convection ◽  
Coefficient Distribution ◽  
Separation Ratio ◽  
Diffusion In Porous Media ◽  
Vertical Cavity

Thermal diffusion, or Soret effect, in porous media is mathematically modeled with the Firoozabadi model based on non-equilibrium thermodynamics. The Soret effect in a binary mixture is investigated in a vertical cavity with heterogeneous permeability, where natural convection can occur. The thermo solutal convection with heterogeneous permeability was studied in terms of flow pattern, concentration distribution, component separation ratio, and Soret coefficient distribution. A consistent analysis was conducted and it is concluded that the Soret coefficient of thermal diffusion in porous media strongly depends on the heterogeneity of permeability.

Gaseous Diffusion in Porous Media. IV. Thermal Diffusion

1964 ◽  
Vol 41 (12) ◽  
pp. 3815-3819 ◽  
Author(s):  
E. A. Mason ◽  
A. P. Malinauskas
Keyword(s):  
Porous Media ◽  
Thermal Diffusion ◽  
Gaseous Diffusion ◽  
Diffusion In Porous Media

scholarly journals Natural Convection And Soret Effect In A Multi-Layered Liquid And Porous System

2021 ◽  
Author(s):  
Hussam K. Jawad
Keyword(s):  
Natural Convection ◽  
Opposite Sign ◽  
Soret Effect ◽  
Fluid Mixing ◽  
Soret Coefficient ◽  
Hydrocarbon Mixture ◽  
Porous System ◽  
Layer System ◽  
Separation Ratio ◽  
Water Alcohol

We investigated the onset of natural convection and thermodiffusion in an initially quiescent multi-layer system consisting of a porous layer sandwiched between two layers of a binary mixture, while the whole system is being heated from above. Two different water-alcohol mixtures were used with Soret coefficients of opposite sign. Then in similar situation a hydrocarbon mixture were investigated. It was found that when the Soret coefficient is negative, the lighter species migrates towards the colder surface while the denser species migrates towards the hotter surface. When the Soret coefficient is positive, the lighter species migrates towards the hotter surface while the denser species migrates towards the colder surface. Also, increasing the temperature difference leads to a greater separation of the mixture components because of the increase in the density gradient. In addition, increasing the porosity reduces the separation ratio due to the increased fluid mixing in the pores.

scholarly journals Natural Convection And Soret Effect In A Multi-Layered Liquid And Porous System

2021 ◽  
Author(s):  
Hussam K. Jawad
Keyword(s):  
Natural Convection ◽  
Opposite Sign ◽  
Soret Effect ◽  
Fluid Mixing ◽  
Soret Coefficient ◽  
Hydrocarbon Mixture ◽  
Porous System ◽  
Layer System ◽  
Separation Ratio ◽  
Water Alcohol

We investigated the onset of natural convection and thermodiffusion in an initially quiescent multi-layer system consisting of a porous layer sandwiched between two layers of a binary mixture, while the whole system is being heated from above. Two different water-alcohol mixtures were used with Soret coefficients of opposite sign. Then in similar situation a hydrocarbon mixture were investigated. It was found that when the Soret coefficient is negative, the lighter species migrates towards the colder surface while the denser species migrates towards the hotter surface. When the Soret coefficient is positive, the lighter species migrates towards the hotter surface while the denser species migrates towards the colder surface. Also, increasing the temperature difference leads to a greater separation of the mixture components because of the increase in the density gradient. In addition, increasing the porosity reduces the separation ratio due to the increased fluid mixing in the pores.

scholarly journals Experimental Investigation of Thermal Diffusion in Binary and Ternary Hydrocarbon Mixtures

2021 ◽  
Author(s):  
Seyyed Arash Mousavi
Keyword(s):  
Thermal Diffusion ◽  
Soret Effect ◽  
Measurement Instrument ◽  
Optical Interferometry ◽  
Temperature Fields ◽  
Soret Coefficient ◽  
Hydrocarbon Mixtures ◽  
Space Experiments ◽  
Convective Motions ◽  
Laser Sources

In a multi-component liquid mixture, the process of disassociation of the components induced by thermal gradient is called thermal diffusion or Soret effect. This effect plays a crucial role in separation of the components in hydrocarbon mixtures of oil. Accordingly, the main goal of this study is to experimentally investigate the Soret effect in binary and ternary hydrocarbon mixtures. Optical interferometry technique with Mach-Zehnder scheme was used to conduct the experiments. The interferometry techniques are not intrusive and the separation of the components in the mixture is not affected by the measurement instrument. A Soret cell is defined as a cubic cavity where the sample mixture is placed in it and, the separation of the components takes place in the cell by heating it from the above. Soret cells are used in convectionless experiments and natural convections are undesirable. The Soret cell used in space experiments was re-designed and optimized for ground-based experiments to avoid the natural convections. Computational studies were made on the both cells to obtain the temperature and velocity fields. Then a set of thermal diffusion experiments conducted in order to compare the performance of the cells. The results shows that the induced convective motions in the second cell are significantly weaker than those in the previous cell which is desirable. In the next step, the effect of the inclination of the cell on the thermal diffusion was studied. First numerical analysis was made to find the velocity and temperature fields in different inclinations and then a set of experiments was performed and the concentration distribution of the components in a binary mixture in different inclinations of the cell was found. Finally, ground based experiments were performed to study the thermal diffusion in five ternary hydrocarbon mixtures. Optical interferometry with Mach-Zehnder scheme using two laser sources with different wavelengths was used. The Soret information of one of the mixtures is available in the literature and this mixture was studied here to validate the present experimental setup. The temperature and concentration of the mixtures were measured successfully in the Soret cell and a table of the measured Soret coefficient were provided.

Modeling Soret coefficient measurement experiments in porous media considering thermal and solutal convection

2001 ◽  
Vol 44 (7) ◽  
pp. 1285-1297 ◽  
Author(s):  
L.B. Benano-Melly ◽  
J.-P. Caltagirone ◽  
B. Faissat ◽  
F. Montel ◽  
P. Costeseque
Keyword(s):  
Porous Media ◽  
Soret Coefficient ◽  
Solutal Convection ◽  
Coefficient Measurement

Thermosolutal convection of a nanofluid in ∧-shaped cavity saturated by a porous medium

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Abdelraheem M. Aly ◽  
Zehba Raizah
Keyword(s):  
Porous Medium ◽  
Porous Media ◽  
Circular Cylinder ◽  
Volume Fraction ◽  
Heterogeneous Porous Media ◽  
Thermosolutal Convection ◽  
Content Type ◽  
Solutal Convection ◽  
Buoyancy Ratio ◽  
Darcy Parameter

Purpose The purpose of this study is to simulate the thermo-solutal convection resulting from a circular cylinder hanging in a rod inside a ∧-shaped cavity. Design/methodology/approach The two dimensional ∧-shaped cavity is filled by Al2O3-water nanofluid and saturated by three different levels of heterogeneous porous media. An incompressible smoothed particle hydrodynamics (ISPH) method is adopted to solve the governing equations of the present problem. The present simulations have been performed for the alteration of buoyancy ratio (−2≤N≤2), radius of a circular cylinder (0.05≤Rc≤0.3), a height of a rod (0.1≤Lh≤0.4), Darcy parameter (10−3≤Da≤10−5), Lewis number (1≤Le≤40), solid volume fraction (0≤ϕ≤0.06), porous levels (0≤η1=η2≤1.5)and various boundary-wall conditions. Findings The performed numerical simulations indicated the importance of embedded shapes on the distributions of temperature, concentration and velocity fields inside ∧-shaped cavity. Increasing buoyancy ratio parameter enhances thermo-solutal convection and nanofluid velocity. Adiabatic conditions of the vertical-walls of ∧-shaped cavity augment the distributions of the temperature and concentration. Regardless the Darcy parameter, a homogeneous porous medium gives the lowest values of a nanofluid velocity. Originality/value ISPH method is used to simulate thermo-solutal convection of a nanofluid inside a novel ∧-shaped cavity containing a novel embedded shape and heterogeneous porous media.

scholarly journals Experimental Investigation of Thermal Diffusion in Binary and Ternary Hydrocarbon Mixtures

2021 ◽  
Author(s):  
Seyyed Arash Mousavi
Keyword(s):  
Thermal Diffusion ◽  
Soret Effect ◽  
Measurement Instrument ◽  
Optical Interferometry ◽  
Temperature Fields ◽  
Soret Coefficient ◽  
Hydrocarbon Mixtures ◽  
Space Experiments ◽  
Convective Motions ◽  
Laser Sources

In a multi-component liquid mixture, the process of disassociation of the components induced by thermal gradient is called thermal diffusion or Soret effect. This effect plays a crucial role in separation of the components in hydrocarbon mixtures of oil. Accordingly, the main goal of this study is to experimentally investigate the Soret effect in binary and ternary hydrocarbon mixtures. Optical interferometry technique with Mach-Zehnder scheme was used to conduct the experiments. The interferometry techniques are not intrusive and the separation of the components in the mixture is not affected by the measurement instrument. A Soret cell is defined as a cubic cavity where the sample mixture is placed in it and, the separation of the components takes place in the cell by heating it from the above. Soret cells are used in convectionless experiments and natural convections are undesirable. The Soret cell used in space experiments was re-designed and optimized for ground-based experiments to avoid the natural convections. Computational studies were made on the both cells to obtain the temperature and velocity fields. Then a set of thermal diffusion experiments conducted in order to compare the performance of the cells. The results shows that the induced convective motions in the second cell are significantly weaker than those in the previous cell which is desirable. In the next step, the effect of the inclination of the cell on the thermal diffusion was studied. First numerical analysis was made to find the velocity and temperature fields in different inclinations and then a set of experiments was performed and the concentration distribution of the components in a binary mixture in different inclinations of the cell was found. Finally, ground based experiments were performed to study the thermal diffusion in five ternary hydrocarbon mixtures. Optical interferometry with Mach-Zehnder scheme using two laser sources with different wavelengths was used. The Soret information of one of the mixtures is available in the literature and this mixture was studied here to validate the present experimental setup. The temperature and concentration of the mixtures were measured successfully in the Soret cell and a table of the measured Soret coefficient were provided.

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