Stall Behavior of the HINVA KH-A320-HA Highlift Model in ETW

Abstract

The objective of the joint research project HINVA (High-Lift In-Flight Validation) funded by the German Federal Ministry of Economics and Technology within the fourth Aeronautical Research Program LuFo IV is to significantly enhance the accuracy and reliability of both numerical and experimental simulation methods with respect to the aerodynamic performance prediction of civil transport aircraft with deployed high-lift devices. To achieve this goal, the most advanced computational fluid dynamics (CFD) and wind tunnel simulation methods currently in industrial use are to be validated against flight test data. DLR’s Airbus A320-200 Advanced Technology Research Aircraft (ATRA) serves as a common configurative basis for the three fields of methodology 1) flight test, 2) high Reynolds-number testing in the European Transonic Windtunnel (ETW), and 3) numerical simulation using DLR’s TAU code. Within the test campaign in ETW Reynolds-number scaling effects on maximum lift of the landing configuration were assessed as well as the influence of small geometric features such as an outboard nacelle strake and an enlarged slathorn. To analyze the aerodynamic effects in detail, integral force measurements were accompanied with surface pressure measurements, aerial Particle Image Velocimetry measurements and transition measurements using temperature sensitive paint. Measurements of the distribution of twist and bending of the model at different levels of total pressure finally allowed to achieve a very high geometric similarity to the flight-test reference on the one hand and on the other hand an assessment of the influence of deviations from the targeted distribution on maximum lift and the associated angle of attack.