Developing and testing an OpenFOAM model to solve the conjugate heat and mass transfer problem

Purpose Conjugate heat and mass transfer between a solid and its surrounding fluid is a problem of widespread importance in environmental and engineering applications. However, popular CFD packages like OpenFOAM overlook mass transport as an active agent that can influence heat transfer through evaporation. Design/methodology/approach In this research, a combined heat–mass transfer OpenFOAM solver is developed and tested. The model was based on the chtMultiRegionFoam solver, where a mass transport equation was involved. The solid mass diffusivity was set as a function of temperature. Furthermore, two interfacial conditions were devised to account for the heat–mass interaction at the interface. The model was utilized to simulate heat and mass transfer in a convective food drying process. A semi-cylindrical carrot sample with a 10 mm diameter and 60 mm length was used as the food material. Findings The results were validated with experimental data from the literature. Ignoring the material–thermal interaction leads to large discrepancies from the actual case. Originality/value This research investigates upgrading the ready chtMultiRegionFoam solver to actively simlate mass transport. The solver has to be inherently modified to account for the evaporation/condensation processes adjointing mass transport. Besides, the devised mass transport process has to be related to the thermal conditions through the solid and fluid properties. Finally, modified interfacial conditions were implemented to adequately simulate the heat and transfer processes at the solid–fluid interface.