Numerical Simulation of Wake Vortices Generated by an A330-200 Aircraft in the Nearfield Phase

In order to overcome the typical limitation of earlier studies, where the simulation of aircraft wake vortices was essentially based on the half-model of symmetrical rectangular wings, in the present analysis the entire aircraft (a typical A330-200 aircraft) geometry is taken into account. Conditions corresponding to the nearfield phase (take-off and landing) are considered assuming a typical attitude angle of 7 degrees and different crosswind intensities, i.e., 0, 2 and 5 m/s. The simulation results show that the aircraft wake vortices form a structurally eudipleural four-vortex system due to the existence of the sweepback angle. The vortex pair at the outer side is induced by the pressure difference between the upper and lower surfaces of the wings. The wingtip vortex is split at the wing by the winglet into two smaller streams of vortices, which are subsequently merged 5 m behind the wingtip. Compared with the movement trend of wake vortices in the absence of crosswind, the aircraft wake vortices move as a whole downstream due to the crosswind to be specific, the 2 m/s crosswind can accelerate the dissipation of wake vortices and is favorable for the reduction of the aircraft wake separation. The 5 m/s crosswind results in significantly increased vorticity of two vortex systems: the wingtip vortex downstream the crosswind and the wing root vortex upstream the crosswind due to the energy input from the crosswind. However, the crosswind at a higher speed can accelerate the deviation of wake vortices, and facilitate the reduction in wake separation of the aircraft taking off and landing on a single-runway airport.