Uncertainty quantification of limit-cycle oscillations

Journal Article · Fri Sep 01 00:00:00 EDT 2006 · Journal of Computational Physics

DOI:https://doi.org/10.1016/j.jcp.2006.03.038· OSTI ID:20840344

Beran, Philip S ^[1]; Pettit, Chris L ^[2]; Millman, Daniel R ^[3]

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1. Multidisciplinary Technologies Center, Air Vehicles Directorate, AFRL/VASD, Building 146, 2210 Eighth Street, WPAFB, OH 45433 (United States)
2. United States Naval Academy, 590 Holloway Rd., MS 11-B, Annapolis, MD 21402 (United States)
3. USAF TPS/EDT, 220 South Wolfe Ave, Bldg. 1220, Rm. 131, Edwards AFB, CA 93524-6485 (United States)

Different computational methodologies have been developed to quantify the uncertain response of a relatively simple aeroelastic system in limit-cycle oscillation, subject to parametric variability. The aeroelastic system is that of a rigid airfoil, supported by pitch and plunge structural coupling, with nonlinearities in the component in pitch. The nonlinearities are adjusted to permit the formation of a either a subcritical or supercritical branch of limit-cycle oscillations. Uncertainties are specified in the cubic coefficient of the torsional spring and in the initial pitch angle of the airfoil. Stochastic projections of the time-domain and cyclic equations governing system response are carried out, leading to both intrusive and non-intrusive computational formulations. Non-intrusive formulations are examined using stochastic projections derived from Wiener expansions involving Haar wavelet and B-spline bases, while Wiener-Hermite expansions of the cyclic equations are employed intrusively and non-intrusively. Application of the B-spline stochastic projection is extended to the treatment of aerodynamic nonlinearities, as modeled through the discrete Euler equations. The methodologies are compared in terms of computational cost, convergence properties, ease of implementation, and potential for application to complex aeroelastic systems.

• OSTI ID: 20840344
• Journal Information: Journal of Computational Physics, Vol. 217, Issue 1; Other Information: DOI: 10.1016/j.jcp.2006.03.038; PII: S0021-9991(06)00187-2; Copyright (c) 2006 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-9991
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
AIRFOILS
BALANCES
CHAOS THEORY
CONVERGENCE
EQUATIONS
EXPANSION
INCLINATION
LIMIT CYCLE
NONLINEAR PROBLEMS
OSCILLATIONS
PITCHES
POLYNOMIALS
STOCHASTIC PROCESSES