The CRM-HL Ecosystem - DLR Contributions

Abstract

With the aim to collect tailored aerodynamic and aero-acoustic data to validate computational fluid dynamics (CFD) methods as well as to improve the understanding of wind tunnel installation effects, DLR carried out experimental investigations of the NASA Common Research Model in high lift configuration (CRM-HL) in the low speed wind tunnel DNW-NWB in Braunschweig. The data are collected and analyzed as part of the DLR project ADaMant. The 5.2% scaled version of the CRM-HL semi span model has been selected as a baseline model configuration. The test campaign is split in two blocks with the first focusing on aerodynamic aspects in the maximum lift regime using the closed test section and the second block utilizing the open test section, which serves to investigate the impact of the test section scenario, but also to carry out aero-acoustic measurements. The aerodynamic tests feature the measurement of forces and moments and static surface pressure data on the model. Transition has been determined on the leading edge devices using infrared thermography. Aerial velocity measurements have been carried out using PIV on selected areas of the flow field of the configurations. The measurements in the open test section have provided forces and moments, as well as pressure distributions over the whole lift regime up to and including CL,max. The acoustic properties are determined by microphone arrays and single microphone measurements. Wall array measurements have also been carried out in the closed test section. Next to the original NASA CRM-HL model, a configurative variation with a vented foldable Krueger flap and a UHBR-through flow nacelle with adapted pylon have been investigated in both test sections. An overview of the model modification and selected results of the different measurement techniques is presented.