AERODYNAMIC WAKE INVESTIGATIONS OF HIGHLIFT TRANSPORT AIRCRAFT WITH DEPLOYED SPOILERS

摘要

Commercial Transport Aircraft (CTA) make use of spoilers in the approach phase. In doing so, the aerodynamic wake of the CTA's wing is highly influenced by the deployed spoilers, potentially leading to horizontal tail plane (HTP) buffet. Mean and turbulent flow field quantities downstream of a CTA model's wing are investigated experimentally to evaluate the near field wake. The used detailed half model features slats, aileron and flaps in high-lift approach configuration. Spoiler configurations comprise a baseline configuration with no spoilers deployed, a configuration with outboard conventional spoilers deployed by δ= 30°, and two configurations, with two types of unconventional outboard spoilers. The experiments are performed in Wind Tunnel A at the Institute of Aerodynamics, Technische Universit?t München. Angles of attack are chosen for each configuration corresponding to a lift coefficient of C_L=1.5. The freestream velocity is set to V_∞ = 50 m/s corresponding to a Reynolds number based on wing mean aerodynamic chord of Re = 1×10~6. Two stream wise positions are chosen to evaluate the evolution of the wake from near the trailing edge of the wing to the tail of the model. Stereo Particle Image Velocimetry is used to measure the velocity distribution in the wake planes. At selected positions of the planes additional velocity measurements are taken by means of Constant Temperature Hot- Wire Anemometry. These time-resolved measurements serve to conduct a spectral analysis. It is shown that the wake of none of the three investigated spoiler configurations does impose a significant increase of vertical turbulence intensity on the HTP; neither broadband nor narrowband.