Akademik Veri Yönetim Sistemi
40th AIAA Fluid Dynamics Conference, cilt.1, 2010 (Scopus)
This paper investigates the effect of chordwise modulated tip injection on the flow and turbulence characteristics of the tip vortex through experimental measurements downstream of a rectangular half-wing that has an aspect ratio of three. This injection technique involves spanwise jets at the tip that are issued from a series of holes along the chord line normal to the freestream flow direction. The injection mass flow rate from each hole is individually controlled using computer driven solenoid valves and therefore the flow injection geometrical pattern at the tip can be adjusted to any desired waveform shape, and can be steady or pulsed as well as moving or stationary waves along the chord. The measurements are performed in a blow-down wind tunnel using Constant Temperature Anemometry as well as Kiel probe traverses. Current data show consistent trends with previously observed effects of steady uniform tip injection such as the upward and outward motion of the vortex as well as increased levels of turbulence within the vortex core. The vortex size gets bigger with injection and the total pressure levels get reduced significantly near the vortex core. The injection pattern also seems to affect the size of the wing wake as well as the wake entrainment characteristics of the tip vortex. Depending on the injection waveform pattern the helicoidal shape of the tip vortex also seems to get affected. © 2010 by Oguz Uzol.