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Journal of Applied Nonlinear Dynamics 5(3) (2016) 349--371 | DOI:10.5890/JAND.2016.09.007

Jianzhe Huang; David A. Peters

Department of Mechanical Engineering and Materials Science, Washington University in St. Louis, St. Louis, MO 63130, USA

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Abstract

Dynamic wake models have been evolved from the earliest, threedegree- of-freedom models (derived from momentum theory) to full finite-state models derived from potential flow theory by a formal Galerkin method. These models are widely used in industry, but still have some drawbacks that need to be remedied. These drawbacks include: 1.) lack of good convergence both on the disk and off the disk (one can use one or the other but not both), 2.) poor results downstream in the limit of shallow skew angles, 3.) poor convergence inside of the rotor wake, 4.) lack of the effect of wake contraction. In this paper, a blended model adopted applications of adjoint theorem, a special change of variables to overcome these obstacles. The resultant model is well behaved in all regimes and is applicable to use in realistic problems of flight simulation.

Acknowledgments

This work was sponsored by the Rotorcraft Centers of Excellence through the Georgia Tech/Washington University Center of Excellence, Drs. Michael Rutkowski and Robert Ormiston, technical monitors.

References

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