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Computational Analysis of Nonlinear Dynamical Systems

M.G.GomanInstitute of Mathematical and Simulation Sciences

De Montfort University, UK

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Contents:

• Nonlinear Dynamics Problems in Aeronautics- Multi-Attractor Aircraft Dynamics (computational study)

- Aerodynamic Asymmetry at High Incidence (wind tunnel experiment interpretation)

• KRIT Toolbox for Nonlinear Investigation and Examples of its Application

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Expanding the Frontiers of |Flight

• Performance and flight envelope- stealth, agility, high capacity and light structures, high incidence, etc.

• Active control technologies, multidisciplinary integrated design, nonlinear mathematical models and methods of analysis.

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Beyond the Normal Flight

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Nonlinear Aircraft Dynamics Problems

• Critical flight regimes investigation

• Closed-loop system dynamics analysis

• Assistance in piloted simulation

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Aircraft Rigid Body Dynamics

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KRIT Toolbox for Nonlinear Dynamics Analysis

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Multi-Attractor Dynamics Investigation (1)

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Multi-Attractor Dynamics Investigation (2)

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Phase Portrait Invetigation

• Steady flight regimes:- normal flight (equilibria);- critical regimes: wing-rock, spin, roll- coupled inertia rotation (equilibria, closed-orbits, toroidalmanifolds, chaotic attractors)

• Regions of attraction:- boundaries of attraction regions- two-dimensional cross sections

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KRIT GUI for Continuation

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KRIT GUI for Phase Portrait Design

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KRIT GUI for Numerical Simulation

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Conclusions:

• The KRIT Toolbox in Matlab provides a broad range of numerical procedures and graphical user interfaces (GUI) for: - nonlinear aircraft dynamics study at high angles of attack, - post-design control laws assessment - assistance in piloted simulation

• The work was funded during last several years by DefenceEvaluation and Research Agency of MoD, UK

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High Incidence Flight Problems Interconnection