UNMANNED AERIAL VEHICLE AERODYNAMICS PERFORMANCE OPTIMIZATION USING VARIABLE SWEEP WING ANGLE

The unmanned aerial vehicles (UAVs) can take many forms depending on the type of UAVduty and condition of flight. In this project, optimization of UAVs aerodynamics property throughthe sweep angle of wing (sweepback angle) to reduce wave drag and delay the onset of drag divergence.therefor models of unmanned aerial vehicles (UAVs) designed with five different sweepbackwing angle (15o, 20o, 25o, 30o, and 35o) and different aspect ratio with constant taper ratio =0.2 have been used. Every wing was built with airfoil for root and tip chord SD8020, with lowMach number equal to 0.058 (i.e., Velocity equal to 20 m/s). The whole models of a wing wereplotted for a three-dimensional using the SOLIDWORKS software program, and then the modelsof this wing were analyzed employing ANSYS FLUENT. Calculations of the value of lift to dragratio were made for deciding which UAV has optimum value of lift and the lowest drag versus theattack angle (0o, 2o, and 4o). The results Show that the aerodynamics performance changes accordingto the value of the sweepback angle and aspect ratio, the maximum lift to drag ratioachieved at UAV with sweepback angle 15o and the angle of attack is 2o, minimum lift to dragratio at UAV with sweepback angle 35o and the angle of attack is 0o. Due to constant taper ratiowhich equal to 0.2 the wing area different according to each model. Best model with maximum liftto drag ratio has wing area equal to 1.68 m2 while model with minimum lift to drag has wing areaequal to 0.65 m2.