Also, when I refine the mesh, the problems appear in different places, where there was no problem with a coarser mesh. If anybody could help me (with any of the three approaches) that would be awesome. I am modeling a thernal shock process of a Ag-SnO2 composite on a representative cell. The zero stress state starts from 800 C, and then cooling to room temperautre.Īs the CTE of Ag and SnO2 are very different, the thermal stress induces. The SnO2 is considered always in elastic, while the Ag is considered as plastic.įor simplify the model, I use the perfect plasticity, with a von mises stress yield function and a constant initial yield stress (55e6). The model runs convergely, as the volume shrinks during the cooling. However, as I processing the average von mises stress of the Ag, the pattern does not increase smoothly but in a sawtooth shape. Meanwhile, the volumetric plastic strain does not increasely, but grows in a repeating step-grow pattern as shown in the images. In principle, the von mises and the volumetric plastic strain should increase gradually, at least not increase by steps. Module load COMSOL comsol batch -inputfile mymodel.mph -outputfile out_12.mph -pname L -plist 12 Module load COMSOL comsol batch -inputfile mymodel.mph -outputfile out_10.mph -pname L -plist 10 So I wander if the changing directions of the principle stretch is related to this strange behaviors.Module load COMSOL comsol batch -inputfile mymodel.mph -outputfile out_8.mph -pname L -plist 8 I find the principle stretchs are growing gradually, but the directions of the principle stretchs in space is changing. Which would run three versions of the study using different values of L and save their outputs in separate files.īe careful to provide a different output file for each line to avoid clashes between the separate jobs. More details can be found on the COMSOL documentation site. Two COMSOL modules (Heat Transfer and Structural Mechanics) are included in addition to the main multiphysics engine. The following models might be solved using our COMSOL package both in stationary and time dependent studies.ĪC/DC. Electric Currents and Electrostatics in 1D, 2D, 3D models. Pressure acoustics in frequency domain in 1D, 2D, 3D models.Ĭhemical Species Transport. Transport of Diluted Species in 1D, 2D, 3D models.
Transport and reactions of the species dissolved in a gas, liquid, or solid can be handled with this interface. The driving forces for transport can be diffusion, convection when coupled to a flow field, and migration, when coupled to an electric field. Moisture Transport in 1D, 2D, 3D is used to model moisture transfer in a porous medium.įluid Flow. Single Phase Laminar and Turbulent Flow including non-isothermal flow in 2D, 3D models.