Experimental Investigation of Effects of Split Blended Winglet on Drag Coefficient of Micro-Aerial Vehicle

There are several ways to increase the aerodynamic efficiency ratio of the wing. One of the most important ones is the use of winglet at the tip of a finite wing. In the present study, four split blended winglets with different upper winglet height mounted on RQ170 Micro-Aerial Vehicle half model and its effects on the drag reduction in zero angles of attack compared with wing without winglet in low Reynolds number. Also, the effect of split blended winglet in different Reynolds number and angles of attack were investigated experimentally. The tests were carried out in a wind tunnel with a low speed and turbulence. The Reynolds number based on the Mean Aerodynamic Chord is changed from 22000 to 46500, and the angle of attack is adjusted from 0◦ to 20◦. The results are representing the drag reduction in all Reynolds number and angles of attack due to using split blended winglet. It was found that with increasing Reynolds number at zero angles of attack, the drag coefficient decreases. Also, the installation of the split blended winglet with the 3cm height of upper winglet has more reduction in total drag coefficient.