Proceedings Article | 8 September 2011
KEYWORDS: Unmanned aerial vehicles, Reconnaissance, Reconnaissance systems, Fluid dynamics, Aerodynamics, Physics, Cameras, Visible radiation, Video, Infrared cameras
In the modern war, UAV(unmanned aircraft system) plays a more and more important role in the army.
UAVs always carry electrical-optical reconnaissance systems. These systems are used to accomplish
the missions of observing and reconnaissance the battlefield. For traditional UAV, the shape of the pod
on UAV is sphericity. In addition, the pod of UAV not only has the job of observing and reconnaissance
the battlefield, but its shape also has impact on the UAV's drag when it flies in the air. In this paper,
two different kinds of pod models are set up, one is the traditional sphericity model, the other is a new
model. Unstructured grid is used on the flow field. Using CFD(computational fluid dynamic) method,
the results of the drags of the different kinds of pod are got. The drag's relationship between the pod
and the UAV is obtained by comparing the results of simulations. After analyzing the results we can get:
when UAV flies at low speed(0.3Ma~0.7Ma), the drag's difference between the two kinds of pod is
little, the pod's drag takes a small part of the UAV's whole drag which is only about 14%. At transonic
speed(0.8Ma~1.2Ma), the drag's difference between these two kinds of pod is getting bigger and bigger
along with the speed goes higher. The traditional pod's drag is 1/3 of the UAV's whole drag value, but
for the new pod, it is only 1/5. At supersonic speed(1.3Ma~2.0Ma), the traditional pod's drag goes up
rapidly, but the new kind of pod's drag goes up slowly. This makes the difference between the two
kinds of UAVs' total drag comes greater. For example, at 2Ma, the total drag of new UAV is only 2/3 of
the traditional UAV. These results show: when the UAV flies at low speed, these two kinds of pod have
little difference in drag. But if it flies at supersonic speed, the pod has great impact on the UAV's total
drag, so the designer of UAV's pod should pay more attention on the out shape.
