Calculation of N-factors for TS and CF disturbances using F100 flight test data

Abstract

The N-factor method has been used to analyse the 60 priority 1-4 data points from the F100 flight tests according to the incompressible stability theory without surface curvature terms. 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 DLR was committed to analyse the instability in the whole wave propagation sector between local main flow and cross flow direction for 5 of the 20 priority 1 test data. These parameter studies confirmed the usefulness to correlate these 2 classical instability types in form of an N**(N**) diagram.