The lid-driven cavity revisited: Stability of two-dimensional flow

The lid-driven cavity has been studied quite extensively both experimentall y and numerically. Today it is the most wide-spread benchmark problem in CF D. Despite this fact, the linear stability of the steady two-dimensional fl ow has hardly been considered, not even for the square cavity. In the prese nt study we revisit this classical problem and calculate the linear stabili ty of the two-dimensional flow with respect to three-dimensional perturbati ons for various aspect ratios. The structure of the critical modes as well as the instability mechanism are addressed.