title: Transient growth of Ekman-Couette flow.
abstract: Coriolis force effects on shear flows are important in geophysical and astrophysical contexts. We report a study on the linear stability and the transient energy growth of the plane Couette flow with system rotation perpendicular to the shear direction. External rotation causes linear instability. At small rotation rates, the onset of linear instability scales inversely with the rotation rate and the optimal transient growth in the linearly stable region is slightly enhanced ∼Re2. The corresponding optimal initial perturbations are characterized by roll structures inclined in the streamwise direction and are twisted under external rotation. At large rotation rates, the transient growth is significantly inhibited and hence linear stability analysis is a reliable indicator for instability.
authors.affiliation: Max Planck Institute for Dynamics and Self-Organization, 37077 Göttingen, Germany and Institute of Geophysics, University of Göttingen, 37077 Göttingen, Germany.
authors.forename: Liang
authors.initials: L
authors.lastname: Shi
authors.affiliation: Max Planck Institute for Dynamics and Self-Organization, 37077 Göttingen, Germany and IST Austria, 3400 Klosterneuburg, Austria.
authors.forename: Björn
authors.initials: B
authors.lastname: Hof
authors.affiliation: Institute of Geophysics, University of Göttingen, 37077 Göttingen, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Tilgner