A Flow Visualization and Aerodynamic Force Measurement of Non-Slender Delta Wing

The non-slender delta wing planforms with 45 degrees sweep angle are highly suitable for use in UAVs and MAVs. The flow pattern over such a delta wing has been studied by surface oil flow visualization technique and the force measurement has been carried out with the help of strain gauges. The surface oil flow figures clearly shows the presence of counter rotating vortices and secondary vortices on two half spans and the vortex breakdown at high angle of attack. The force measurement shows the increased lift and drag due to these vortices and the vortex breakdown respectively. The interesting post-stall area in this delta wing showed an increased lift coefficient, which is different than the conventional wings and their associated sudden, deep stall, a trade mark of Delta Wings. The Reynolds number of the experiment was around 4 x 10(5).