Experimental Investigation of Tollmien-Schlichting Instability and Transition in Similar Boundary Layer Flow in an Adverse Pressure Gradient (Hartree beta = -0.14)

摘要

The results are presented of a two dimensional experimental investigation of the region of validity of linear stability theory in boundary layer flow, under natural disturbance conditions. Experimental results are compared with two quasi-parallel linear stability computer programs. The first is part of the low speed airfoil analysis and design code of the Low Speed Laboratory (LSL) of the University of Technology Delft (TUD), using tabulated linear stability data. The second program is a finite difference compressible temporal linear stability code, based on Cosal, of the National Aerospace Laboratory (NLR). The experimental investigations were performed at LSL on the 2m long flat test wall of a small open ended boundary layer wind tunnel with a flexible opposite wall to generate a desired pressure gradient.