Active nematic fluids with flow alignment

Abstract

We derive a stream function formulation for the dynamics of 2D active nematics in the absence of topological defects. This formulation extends previous studies by incorporating the flow alignment coupling. We study the linear stability analysis of the spontaneous-flow instability and check it numerically. Then, we obtain numerically the 2D nonlinear stationary states for a particular limit in which active forces dominate over elastic ones, and viscous dissipation dominates over rotational dissipation. Finally, we find significant differences with previous results due to the presence of the flow alignment coupling