Papers Published

1. Rule, John A. and Epstein, Ronald J. and Bliss, Donald B., Unsteady compressible boundary element calculations of parallel blade-vortex interaction, Journal of the American Helicopter Society, vol. 44 no. 4 (1999), pp. 302 - 311 .
   (last updated on 2007/04/09)

   Abstract:
   A method for calculating parallel blade vortex interaction (BVI) has been developed. The technique is based on the application of a three-dimensional aeroacoustic boundary element formulation using Analytical/Numerical Matching in conjunction with a recently developed viscous core trailing vortex roll-up model. Computational parameters were chosen to correspond with an experimental investigation conducted at NASA Ames Research Center modeling parallel BVI between a model rotor and an independently generated trailing vortex. Calculations include rotor blade chordwise pressure distributions, blade surface pressure time histories, and both near- and far-field radiated acoustic pressure time histories. Comparisons with experimental data demonstrate the feasability of applying linear theory to the study of BVI.

   Keywords:
   Boundary element method;Flow interactions;Vortex flow;Mathematical models;Unsteady flow;Compressible flow;Pressure distribution;