InterPore2021

Coupled LBM-MHFEM simulator for vapor transport in air over a moist soil layer

2 Jun 2021, 10:00

1h

Poster (+) Presentation (MS7) Mathematical and numerical methods for multi-scale multi-physics, nonlinear coupled processes Poster +

Speaker

Jakub Klinkovský (Department of Mathematics, Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University in Prague)

Description

We present an efficient computational approach for simulating component transport within single-phase free flow over a soil. A numerical model based on this approach was validated using controlled experiments in a climate-controlled low-speed wind tunnel. The wind tunnel is interfaced with a soil tank to study problems of heat and mass flux across the land-atmospheric interface. The developed modeling approach is based on a combination of the lattice Boltzmann method (LBM) formulated for weakly compressible fluid flow and the mixed-hybrid finite element method (MHFEM) for solving constituent transport. Both those methods individually, as well as when coupled, are implemented entirely on a GPU accelerator in order to utilize its computational power and avoid the hardware limitations that slow communication between the GPU and CPU over the PCI-E bus. We describe the mathematical details behind the computational method, focusing primarily on the coupling mechanisms. Flow and transport simulation results are validated and compared herein with experimentally obtained velocity and relative humidity data based on measurements made above a soil surface over with water evaporates under steady air flow conditions. Model robustness and flexibility is demonstrated by introducing rectangular bluff-bodies to the flow in several different experimental scenarios.