A Numerical Study of a Rotor Induced Flow Based on a Finite-State Dynamic Wake Model.

Authors

DOI:

https://doi.org/10.5540/tcam.2021.022.02.00307

Keywords:

Unsteady wake, eigen-analysis, inflow states.

Abstract

A Helicopter rotor undergoes unsteady aerodynamic loads ruled by the aeroelastic coupling between the elastic blades and the dynamic wake induced by rotary wings. Modeling the dynamic interaction between the structural and aerodynamic fields is a key point to understand aeroelastic phenomena associated with rotor stability, flow induced vibration and noise generation, among others. In this study, we address the Generalized Dynamic Wake Model, which describes the inflow velocity field at the rotor disk as a superposition  of a finite number of induced flow states. It is a mature model that has been validated based on experimental data and numerically investigated from an eigenvalue problem formulation, whose eigenvalues and eigenvectors provide a deeper insight on the dynamic wake behavior. The paper extends the results presented in the literature to date in order to support physical interpretation of inflow states drawn from the finite-state wake model for flight conditions varying from hover to edgewise flight. The discussion of the wake model mathematical formulation is also oriented towards practical engineering applications to fill a gap in the literature.

Author Biographies

L. G. A. Ferreira, São Paulo State University (UNESP)

Câmpus de São joão da Boa Vista

C. C. Pagani Júnior, São Paulo State University (UNESP)

Câmpus de São joão da Boa Vista

E. M. Gennaro, São Paulo State University (UNESP)

Câmpus de São joão da Boa Vista

C. De Marqui Junior, University Of São Paulo (USP)

Aeronautic Engineering

References

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Published

2021-06-28

How to Cite

A. Ferreira, L. G., Júnior, C. C. P., Gennaro, E. M., & Junior, C. D. M. (2021). A Numerical Study of a Rotor Induced Flow Based on a Finite-State Dynamic Wake Model. Trends in Computational and Applied Mathematics, 22(2), 307–324. https://doi.org/10.5540/tcam.2021.022.02.00307

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Original Article