Aeroelastic Research and Unsteady Aerodynamics at DLR.

Kurzfassung

In the first part of the seminar "Aeroelastic Research Activities at DLR" an overview over current work at the DLR Institute of Aeroelasticity in the fields of structural dynamics, aeroelastic stability of wings, nacelles and cascades and unsteady aerodynamic code developments and tests is given. Then those research activities are reviewed, which focus on the main aeronautical guiding configurations, namely flexible transport aircraft with high bypass ratio engines (AIRBUS), adaptive transport wing and propfans. Improvement of aeroelastic prediction depends significantly on progress in aerodynamic code developments. The problem of predicting the transonic dip for a clean transport wing is not yet solved satisfactorily. Other problems like unsteady (shock induced) separation close to the design condition of supercritical wings, interference effects of large engine nacelles as well as static and dynamic deformations of elastic wings have to be taken into account and demand improved unsteady CFD codes. These points were investigated in a comprehensive test on a supercritical transport wing model (Aeroelastic Model Program). Within the currentDLR-project CASWING unsteady aerodynamic codes and flutter prediction methods will be improved and tested in a series of validation experiments, ranging from oscillating airfoils to a wing-nacelle configuration. In a third phase the improved numerical tools will be applied to the project of an Adaptive Transonic Transport Wing.