Effects of Different Shaped Cavities and Bumps on Flow Structure and Wing Performance

The stall of an aircraft is one the most dangerous phenomena in aviation world, resulting a sudden loss lift because boundary layer separation. This work aims to delay separation and improve wing aerodynamic performances by introducing bumps cavities on upper surfaces wing. A numerical study effects both flow structures aerodynamics NACA 0012 profile conducted. CFX code has been used perform calculations steady uncompressible Reynolds Averaged Naviers-Stokes equations. airfoil exposed free stream velocity 5.616 m/s chord based number 3.6 x 105 (chord length). series test unmodified carried out for various turbulence models at angles attack ranging from 0° 15°. Then, two-equation k-ω SST (Shear Stress Transport) retained further cases. Different configurations obtained through modification shape, dimension, position are investigated. Both shapes considered semi-spherical semi-cylindrical, placed two positions chord. first location suction pick X/C= 0.3 second 0.7. Results show that application delays increase drag coefficient. slight enhancement observed angle 15° cases where 0.7 m leading edge. In addition, stability vortex formed inside depends strongly their shape cylindrical better performances.