Determination of the Aerodynamic Characteristics of Low Reynolds Number Flows over Small Uninhabited Aerial Vehicles Authors:

• Main Authors: Hugo T. C. Pedro, Dr. Marcelo, H. Kobayashi
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Humpback Whale
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.523.9220; http://www.hawaii.edu/hpc/pedro_report.pdf

The interest in small-unmanned aerial vehicles (UAV’s) has increased greatly in the past decade. The size of such vehicles and the velocity at which they operate results in low Reynolds (Re) number flight regime, in the 15000 − 500000 range. The high Re aerodynamics is well established, however the same cannot be said for the low Re regime. In this range the wing’s aerodynamic performance can deteriorate rapidly as the Re number decreases. To simply scale the vehicle to a smaller size is not the solution. Further research in this range of Re numbers is necessary. Recently was reported that the humpback whale flipper is optimized to prevent stall and to improve aerodynamic performance. These features allow these animals to be extremely mobile with great turning ability, which is necessary to catch prey. This observation together with the fact that the Reynolds number for the humpback whale falls in the aforementioned low Re range propelled the experimental study the humpback whale flipper. The flippers for this species display a very characteristic scalloped leading edge, whereas the flippers of other species less maneuverable are much smoother. The experiments compared a flipper with tubercles with a smooth flipper. The researchers reported an improvement in the