We explore the effects on grain size distribution of incorporating grain rotation into the curvature driven grain boundary migration model of Mullins. A new, extremely streamlined and efficient algorithm allows simulations with large numbers of grains. Some of these simulations yield size distributions and microstructures close to those from recent, atomistic simulations of microstructural evolution using the phase field crystal method that was shown to reproduce experimental size distributions observed in fiber textured, nanocrystalline, thin metallic films. (C) 2016 Elsevier B.V. All rights reserved.