Microwave Heating at the Grain Level

S. Lefeuvre[1], and O. Gomonova[2]
[1]Eurl Creawave, Toulouse, France
[2]Siberian State Aerospace University, Krasnoyarsk, Russia

The microwave heating and processing of heterogeneous material is usually simulated using a set of coupled PDE equations in an homogeneous medium. Nowadays it is possible to describe more accurately the process with a suitable description of the heterogeneities that is at the grain level. Many authors work with spheres (circles) to represent the grains but it is difficult to achieve an acceptable value of the porosity. This paper shows how it is possible to deal directly with the meshing produced by COMSOL to get a description of the grains and the pores : Let us start with a homogeneous volume and apply a coarse meshing. Then COMSOL is able to produce a doc.txt with the matrices of nodes and elements. The needed value of porosity can be obtained by homothety. Examples in the area of microwave drying and sintering are given in the paper.