Coupled heat and mass transfer in porous media: insight and perspective of multiscale modelling

International audienceThis conference is devoted to multiscale approaches of coupled transfer in porous media, with particular attention to configurations leading to the failure of the assumption of local thermodynamic equilibrium. Upscaling methods, such as homogenization or volume averaging, allowed a well-established set of macroscopic equations to be obtained. This approach is powerful but needs to be supplied by relevant effective parameters. Nowadays, thanks to the spectacular progresses in 3D imaging and computational tools, these effective parameters can be obtained by 3D calculations on real pore morphologies. Recent examples will be presented to predict properties of bio-based building materials. The remaining part of the conference will be devoted to configurations generating the absence of local thermodynamic equilibrium. Such situations, arising more often than expected, require a comprehensive multiscale approach (concurrent coupling). In such configurations, the local history of the product must be embedded in the formulation. Three approaches will be discussed here: - The concept of distributed microstructure models, with various assumptions regarding the coupling between scales, - The transfer of all the information at the micro scale (downscaling), - The transfer of all the information at the macroscopic level, in which the concept of internal variable allows the history of the microscopic field to be transferred at the macroscopic level, Finally, the new trends will be briefly presented: thanks to the impressive development of 3D imaging tools together with High Performance Computers, direct numerical simulation of transfer in porous media will be widely used in the future