CALCULATION OF WAKE VORTEX STRUCTURES IN THE NEAR-FIELD WAKE BEHIND CRUISING AIRCRAFT

Wake flows behind cruising aircraft influence the distribution of the exhaust gases. A three-dimensional vortex filament method was develope d to calculate the vortex structures and the velocity held of the vort icity dominated wake flows as an integration of the Biot-Savart law. F or three-dimensional vortex filament calculations, self-induction sing ularities were prevented using a finite vortex core for each vortex fi lament. Numerical simulations show the vortex structures and the veloc ity field in the wake behind a cruising Boeing 747 as a result of the integration of the Biot-Savart law. It is further shown how the struct ures of the fully rolled-up trailing vortices depend on the wing span loading, i.e. the circulation distribution. (C) 1998 Elsevier Science Ltd. All rights reserved.