OpenFOAM Simulation for Electromagnetic Problems

Abstract

SUMMARY Simulation is considered as one of the most important and cost efficient approach of industry research and development. OpenFOAM is one simulation tool with manual solver compilation ability and 3D calculation capability, used for instance for computational fluid dynamics (CFD) [1]. This thesis work is based on the OpenFOAM ‘rodFoamcase’ and the ‘rodFoam’ solver used for plasma arc welding simulations which calculates the magnetic field in air. The thesis work extends the case and the solver to solve electromagnetic field problems for more materials including copper, linear steel and permanent magnets with different geometries. In the future, this work can be applied into the design procedures of electromagnetic devices, like electrical machines. Based on the Maxwell equations, two different formulations (the A-V formulation and the A-J formulation) are derived to solve magnetrostatic field problems. Formulations are compiled manually into OpenFOAM solvers according to mathematic models by specific program codes. Furthermore, force calculation equations are derived with the Lorenz Force Method and the Maxwell Stress Tensor method. Then, simple geometries with specific initial values and boundary conditions are calculated to test the new solvers. The results of the developed simulation procedures in OpenFOAM are compared to the results of another simulation software; COMSOL Multiphysics. It is found that the simulation results show a very good agreement between OpenFOAM simulations and COMSOL simulations. Prediction of the future utilization of this thesis work and directions of development are also discussed.