Heat and mass transfer in TPMS-based porous media: Two-medium approach
A. I. Popov, Dmitry Mikhailovich Bragin, А. В. Еремин
Abstract
The article presents a study aimed at developing an efficient method for modeling heat and mass transfer in porous materials, including materials with structures based on triply periodic minimal surfaces (TPMS). To describe the heat transfer process, a two-temperature Continuous-Solid model was used, which is based on the heat transfer coefficient between the fluid and solid phases, h f s . The values of the coefficient h f s were determined through a series of computational experiments in ANSYS Fluent under various flow conditions. The main principles of the developed method were considered using the example of a two-dimensional heat and mass transfer problem in a porous material which structure is based on the Schwarz P triply periodic minimal surface. To solve the problem numerically, a program called “ThermoNAS” was developed in the Python programming language, implementing the finite difference method. The program enables plotting temperature contours for both fluid and solid phases, displays the average fluid temperature at the outlet, and shows the overall pressure drop. An interactive interface with time step control allows analysis of the dynamics of the heat transfer process. The source code and executable file of the program are openly available on the Mendeley Data platform. A comparison of the heat transfer simulation results in a porous material obtained using ThermoNAS and ANSYS Fluent showed that for the problem under consideration, the developed program achieves more than 50 times faster computation due to homogenization of the medium without the need to create complex geometry and meshing. At low flow velocities, the discrepancy between ThermoNAS and ANSYS results does not exceed 1 %, whereas at higher velocities, the discrepancy increases, which is explained by the absence of dispersion in the ThermoNAS model. Using the ThermoNAS program, temperature fields in a porous material with a structure based on TPMS Schwarz P were investigated. Pressure losses were determined as a function of the inlet flow velocity, and graphs of the average fluid outlet temperature over time were constructed. The proposed method and the developed program may be useful in various applied problems in energy, oil and gas industries, and medicine for fast modeling of heat and mass transfer processes and determining temperature distribution in porous materials, including those based on TPMS.