Aerodynamic Simulation of Wake Encounter for Aircraft Close Formation Operations (Invited)

Abstract

In this study, the rolling moment coefficient of a following unmanned aerial vehicle (UAV) induced by wake vortices from a leading UAV is analyzed and studied. Numerical simulation results are compared to the results from an analytical vortex lattice method. Then a complete UAV mesh is built and used to calculate the influence by a pair of wake vortices created by the leading UAV in real flight scenario. The paper provides an estimate of the vortex roll hazard assessment for the following UAV in close formation operations. Nomenclature 0 = main wing span = rolling moment coefficient of the follower = cord length of the follower ̅ = average cord length of the follower = rolling moment of the follower = induced vortex core radius = plan form area = wing span = vertical velocity on the wing = flying speed of the follower = coordinate of the main wing of the follower 0 = vortex strength generated by the leader = vortex strength acting on the follower = circulation on the wing of the follower