An architecture for real-time flight simulation of a vortex lattice rotor wake model

A helicopter rotor wake model that is based on tracking vorticity generated by the rotor blades is presented. The model is representative of the style being developed for helicopter wake simulations and is used as a test load for a simulator architecture. For the test wake model, blade elements are treated as lifting lines. The near wake is presented as a vortex lattice and the far wake as vortex rings. The velocity induced by all parts of the wake is used to compute the lift of the blade elements and to drift each part of the wake. A vortex lattice generated by ten rotor revolutions, with vortex rings representing older vorticity was sufficient to reproduce the full induced velocity at the rotor.; A simulator architecture that utilizes parallel processing to operate the wake model in real time is presented. The architecture employs multiple computers connected with a SCRAMNet shared memory network. The system also makes use of multiple processors in each computer. Real-time operation was achieved, while accounting for only tip and root trailing vortices, using sixteen 400 MHz Pentium II processors in parallel.