Experimental and Theoretical Investigation of the Supersonic Boundary Layer Stability on the Swept Wing

Read more Theoretical and an experimental research results of the disturbances development in a swept wing boundary layer are presented at Mach number М = 2. In experiments development of natural and small amplitude controllable disturbances downstream was studied. Experiments were carried out on a swept wing model with a lenticular profile at a zero attack angle. The swept angle of a leading edge was 40°. Wave parameters of moving disturbances were determined. In frames of the linear theory and an approach of the local self-similar mean flow the stability of a compressible three-dimensional boundary layer is studied. Good agreement of the theory with experimental results for transversal scales of unstable vertices of the secondary flow was obtained. However the calculated amplification rates differ from measured values considerably. This disagreement is explained by the nonlinear processes observed in experiment.

Keywords:
supersonic boundary layer, swept wing, instability, wave packets, nonlinearity, laminar-turbulent transition, stationary perturbations.
УДК 532.526

Experimental and Theoretical Investigation of the Supersonic Boundary Layer Stability on the Swept Wing