Low-Speed Testing of the 5.2% Semispan CRM-HL in the DNW-NWB Wind Tunnel

Abstract

In this paper, the wind tunnel test of the 5.2% CRM-HL in the DNW-NWB low speed wind tunnel is described. The tunnel test campaign is settled in the DLR project ADaMant, in which it is of interest to generate qualitative data for CFD validation to improve the predictive accuracy, efficiency, and usability of physical modeling in CFD codes at the borders of the flight envelope. Different configurations of the CRM-HL were tested in a closed and in an open test section of the wind tunnel. Several measurement techniques were used to generate validation data including forces and moments, pressures, flow visualization with tufts and oil paint, and infrared thermography for boundary layer transition detection. The evaluation of the results focuses on these techniques in the closed test section. The test comprises Mach numbers from 0.15 to 0.23 and Reynolds numbers based on mean aerodynamic chord from 1.2x106 to 1.8x106. Some results are also compared to data from the NASA Langley Research Center 14-by-22-Foot subsonic wind tunnel to assess the repeatability of measurements of the same model in different wind tunnels.