  Many technologically useful materials are polycrystals composed of a myriad
of small monocrystalline grains separated by grain boundaries. Dynamics of
grain boundaries play a crucial role in determining the grain structure and
defining the materials properties across multiple scales. In this work, we
consider two models for the motion of grain boundaries with the dynamic lattice
misorientations and the triple junctions drag, and we conduct extensive
numerical study of the models, as well as present relevant experimental results
of grain growth in thin films.
