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Papers by Michel Quintard
Proceeding of Proceedings of Symposium on Energy Engineering in the 21st Century (SEE2000) Volume I-IV
... OF HEAT TRANSFER IN POROUS MEDIA Michel Quintard Institut de Mecanique des Fluides de Toulous... more ... OF HEAT TRANSFER IN POROUS MEDIA Michel Quintard Institut de Mecanique des Fluides de Toulouse Allee du Professeur Camille Soula, 31400 ... fr, Fax:+ 33 5 63 49 30 99 StephenWhitaker Department of Chemical Engineering University of California at Davis, Davis, CA ...
Proceeding of International Heat Transfer Conference 10, 1994
Acid treatment is frequently used in the oil industry to improve well productivity. It is achieve... more Acid treatment is frequently used in the oil industry to improve well productivity. It is achieved in carbonate reservoir by taking advantage of a macroscopic instability which creates empty channels (wormholes) bypassing the damaged areas and improving near wellbore permeability. Length, size and density of these channels depend on numerous parameters from injection rate to rock properties. Resulting dissolution patterns have been extensively studied and several models proposed. Today, core-scale numerical models can successfully reproduce the dissolution physical mechanism, but they are limited in their ability to predict skin effect at the wellbore scale. As a consequence, large-scale models are based on semi-empirical approaches. Productivity improvement resulting from acidizing treatments cannot be predicted unless radial flow and heterogeneities are considered. In this paper, we present a large scale model obtained through upscaling techniques from the core-scale model. The du...
NAPL transport in geological formations is currently receiving a great deal of attention for issu... more NAPL transport in geological formations is currently receiving a great deal of attention for issues such as remediation of contaminated groundwater. NAPL dissolves into the water phase in a process referred to as active dispersion. A Volume Averaging Method has been used to upscale the dispersion phenomenon in presence of a trapped NAPL. Thus, the active dispersion tensor and the mass exchange coefficient are directly related to the micro-scale properties through two pore-scale closure problems. These problems have been solved numerically previously over a unit cell using a finite volume formulation. However, this numerical resolution, based on a detailed discretisation of the pore structure is limited to simple unit cells containing a small number of pores. Results for the macroscopic properties are therefore biased by the chosen particular geometry. In order to take into account a larger number of pores and to obtain more significant results, the pore structure is idealised as a 3...
70% of the contaminated sites in France are with organic compounds (hydrocarbons, chlorinated sol... more 70% of the contaminated sites in France are with organic compounds (hydrocarbons, chlorinated solvents,…). Modeling such contamination can be difficult as it is governed by numerous and highly coupled mechanisms (multiphase flow, dissolution and volatilization of Non Aqueous Phase Liquids(NAPL), sorption and biodegradation). Whereas many numerical codes include some of these mechanisms, none of them, to our knowledge, allows the modeling of the full set of mechanisms. A new code, called M3 for Multiphase, Multicomponent, Multiprocess, is then being developed to address this kind of modeling. The originality of the code stands both in the diversity of the mechanisms and in original formalisms such as non-local equilibrium dissolution of NAPL or biodegradation formalism dedicated to chlorinated solvents. After a short description of the numerical code, test cases will be presented to highlight the capacity of the code to model many situations that might be accoutered when dealing with...
Modeling transport in porous media requires to take into account multiple-scale aspects inherent ... more Modeling transport in porous media requires to take into account multiple-scale aspects inherent to porous media structures. Several methodologies have been developed to upscale the equations at a lower-scale and to obtain upper-scale models. This question is reviewed based on a simple heat conduction problem. This is used to present briefly: volume averaging, homogenization, stochastic approaches, and various variants. Following the guidelines provided by volume averaging, the problem of the emergence of macro-scale equations for momentum and energy balance is discussed, with the emphasis on the existence of different models depending on pore-scale physical properties (dimensionless parameters, various time and length-scale ratios). Finally, extensions to more complicated problems of heat transfer in porous media, characterized by various couplings between transport problems, are briefly discussed: coupling with mass diffusion, effect of heat sources, boiling, etc.
In this paper we consider the transport of a chemical species in a two phase system with exchange... more In this paper we consider the transport of a chemical species in a two phase system with exchange of matter at the interface (so-called active dispersion). The boundary conditions at the interface between the two phases existing within the pore space are either of thermodynamic equilibrium or of reactive type. Saturation changes with the exchange of matter at the interface. The medium itself is characterized by different levels of heterogeneity starting from the pore-scale. In this work, problems related to pore-scale to Darcy-scale upscaling and then to Darcy-scale to Large-scale upscaling are considered. The first upscaling [1] leads to different problems depending on the boundary conditions and various assumptions, in particular the role of the total mass exchange rate, non-standard terms, etc. The role of geometry, reaction rate on dispersion and tortuosity is investigated for simple 1D/2D/3D unit cells. The second upscaling is only considered for the case of a local non-equilib...
Aeration is essential in the composting process because it ensures oxygen transport that is neces... more Aeration is essential in the composting process because it ensures oxygen transport that is necessary to enhance aerobic fermentation. In simplest composting systems, only natural convection due to the waste porosity provides the compost pile ventilation. This limits the process to small piles and composts with very high porosity. Industrial windrow operations need another kind of oxygenation which can be obtained by a mechanical turn around or a forced aeration. In case of forced aeration, the air can be insufflated or sucked. Obtaining good ventilation conditions for the compost allow keeping aerobic conditions for a good degradation of the organic matter (OM), a good temperature rising (so a good hygienisation) and avoiding anaerobic fermentation phenomena that lead to the production of fool-smelling products. Nevertheless, utilization of forced aeration systems can lead to compost drying (especially around the aeration lines) (Diaz & Savage (2003)) depending on the air temperatu...
Proceeding of Proceedings of Symposium on Energy Engineering in the 21st Century (SEE2000) Volume I-IV
... OF HEAT TRANSFER IN POROUS MEDIA Michel Quintard Institut de Mecanique des Fluides de Toulous... more ... OF HEAT TRANSFER IN POROUS MEDIA Michel Quintard Institut de Mecanique des Fluides de Toulouse Allee du Professeur Camille Soula, 31400 ... fr, Fax:+ 33 5 63 49 30 99 StephenWhitaker Department of Chemical Engineering University of California at Davis, Davis, CA ...
Proceeding of International Heat Transfer Conference 10, 1994
Acid treatment is frequently used in the oil industry to improve well productivity. It is achieve... more Acid treatment is frequently used in the oil industry to improve well productivity. It is achieved in carbonate reservoir by taking advantage of a macroscopic instability which creates empty channels (wormholes) bypassing the damaged areas and improving near wellbore permeability. Length, size and density of these channels depend on numerous parameters from injection rate to rock properties. Resulting dissolution patterns have been extensively studied and several models proposed. Today, core-scale numerical models can successfully reproduce the dissolution physical mechanism, but they are limited in their ability to predict skin effect at the wellbore scale. As a consequence, large-scale models are based on semi-empirical approaches. Productivity improvement resulting from acidizing treatments cannot be predicted unless radial flow and heterogeneities are considered. In this paper, we present a large scale model obtained through upscaling techniques from the core-scale model. The du...
NAPL transport in geological formations is currently receiving a great deal of attention for issu... more NAPL transport in geological formations is currently receiving a great deal of attention for issues such as remediation of contaminated groundwater. NAPL dissolves into the water phase in a process referred to as active dispersion. A Volume Averaging Method has been used to upscale the dispersion phenomenon in presence of a trapped NAPL. Thus, the active dispersion tensor and the mass exchange coefficient are directly related to the micro-scale properties through two pore-scale closure problems. These problems have been solved numerically previously over a unit cell using a finite volume formulation. However, this numerical resolution, based on a detailed discretisation of the pore structure is limited to simple unit cells containing a small number of pores. Results for the macroscopic properties are therefore biased by the chosen particular geometry. In order to take into account a larger number of pores and to obtain more significant results, the pore structure is idealised as a 3...
70% of the contaminated sites in France are with organic compounds (hydrocarbons, chlorinated sol... more 70% of the contaminated sites in France are with organic compounds (hydrocarbons, chlorinated solvents,…). Modeling such contamination can be difficult as it is governed by numerous and highly coupled mechanisms (multiphase flow, dissolution and volatilization of Non Aqueous Phase Liquids(NAPL), sorption and biodegradation). Whereas many numerical codes include some of these mechanisms, none of them, to our knowledge, allows the modeling of the full set of mechanisms. A new code, called M3 for Multiphase, Multicomponent, Multiprocess, is then being developed to address this kind of modeling. The originality of the code stands both in the diversity of the mechanisms and in original formalisms such as non-local equilibrium dissolution of NAPL or biodegradation formalism dedicated to chlorinated solvents. After a short description of the numerical code, test cases will be presented to highlight the capacity of the code to model many situations that might be accoutered when dealing with...
Modeling transport in porous media requires to take into account multiple-scale aspects inherent ... more Modeling transport in porous media requires to take into account multiple-scale aspects inherent to porous media structures. Several methodologies have been developed to upscale the equations at a lower-scale and to obtain upper-scale models. This question is reviewed based on a simple heat conduction problem. This is used to present briefly: volume averaging, homogenization, stochastic approaches, and various variants. Following the guidelines provided by volume averaging, the problem of the emergence of macro-scale equations for momentum and energy balance is discussed, with the emphasis on the existence of different models depending on pore-scale physical properties (dimensionless parameters, various time and length-scale ratios). Finally, extensions to more complicated problems of heat transfer in porous media, characterized by various couplings between transport problems, are briefly discussed: coupling with mass diffusion, effect of heat sources, boiling, etc.
In this paper we consider the transport of a chemical species in a two phase system with exchange... more In this paper we consider the transport of a chemical species in a two phase system with exchange of matter at the interface (so-called active dispersion). The boundary conditions at the interface between the two phases existing within the pore space are either of thermodynamic equilibrium or of reactive type. Saturation changes with the exchange of matter at the interface. The medium itself is characterized by different levels of heterogeneity starting from the pore-scale. In this work, problems related to pore-scale to Darcy-scale upscaling and then to Darcy-scale to Large-scale upscaling are considered. The first upscaling [1] leads to different problems depending on the boundary conditions and various assumptions, in particular the role of the total mass exchange rate, non-standard terms, etc. The role of geometry, reaction rate on dispersion and tortuosity is investigated for simple 1D/2D/3D unit cells. The second upscaling is only considered for the case of a local non-equilib...
Aeration is essential in the composting process because it ensures oxygen transport that is neces... more Aeration is essential in the composting process because it ensures oxygen transport that is necessary to enhance aerobic fermentation. In simplest composting systems, only natural convection due to the waste porosity provides the compost pile ventilation. This limits the process to small piles and composts with very high porosity. Industrial windrow operations need another kind of oxygenation which can be obtained by a mechanical turn around or a forced aeration. In case of forced aeration, the air can be insufflated or sucked. Obtaining good ventilation conditions for the compost allow keeping aerobic conditions for a good degradation of the organic matter (OM), a good temperature rising (so a good hygienisation) and avoiding anaerobic fermentation phenomena that lead to the production of fool-smelling products. Nevertheless, utilization of forced aeration systems can lead to compost drying (especially around the aeration lines) (Diaz & Savage (2003)) depending on the air temperatu...