Abstract
The flow behind perforated Gurney-type flaps was investigated by using particle image velocimetry (PIV) at Re = 5.3 × 104. The PIV measurements were supplemented by force balance and surface pressure data. The near wake was disrupted and narrowed, indicative of a reduced drag, with increasing flap perforation and had a drastically suppressed fluctuating intensity. Depending on the strength of the perforation-generated jet, the vortex shedding process behind the flap could be eliminated. The flap porosity also led to reduced positive camber effects and the decompression of the cavity flow (upstream of the flap), as well as decreased upper and lower surface pressures, compared to the solid flap. The reduction in the drag, however, outweighed the loss in lift and rendered an improved lift-to-drag ratio.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
