On the görtler instability of boundary layers

Abstract

Görtler instability occurs due to the action of centrifugal forces in boundary layers over curved surfaces, where it most commonly results in the generation of steady streamwise vortices. This study provides a summary of the current knowledge of this phenomenon. All existing experimental evidence is discussed. Experimental facts that bear on the theoretical modelling of the instability are pointed out. Linear theory is discussed in details and compared critically with the available experiments. The nonlinear evolution of the vortices and their effect on the laminar-turbulent transition process are reviewed. The available nonlinear theories and direct numerical simulations are critically compared with the experiments. Centrifugal instability of turbulent boundary layers is discussed in detail. Effects of the instability on heat transfer and the associated buoyancy forces on the instability are discussed. A summary of some outstanding questions is given.