Stability analysis on S1Ma wind tunnel experiments with suction

Abstract

The N-factor method has been used to analyse 10 run points of previous S1Ma wind tunnel experiments with a HLF half wing model according to the incompressible stability theory without surface curvature terms. In the experiments suction up to 0.25 m/s had been applied individually to totally 15 chambers within the first 12.5% of chord on upper as well lower wing surface. According to DLR's practice to correlate the instability behaviour of traveling waves (Tollmien-Schlichting) and standing waves (Cross Flow) DLR was involved in the strategy methods 2: The fixed frequency and fixed propagation direction and 4: The fixed frequency and fixed wavelength. Furthermore the instability in the whole wave propagation sector between local main flow and cross flow direction for all 10 tests has been assessed.