Orthogonal modes are an effective method for aerodynamic shape optimization due to their excellent design space compactness; however, all existing methods are generated from a database of representative geometry. Moreover, application to high-fidelity design spaces is not possible because high-frequency shape components are insufficiently bounded, leading to nonsmooth and oscillatory geometries. In this work, a new generic methodology for generating orthogonal shape modes is presented based on a purely geometric derivation, eliminating the need for geometric training data. The new method is a further development of the gradient-limiting method developed previously for constraining the design space in a geometrically meaningful way to reduce the effective degrees of freedom and improve optimization convergence rate and final result. Here, the gradient-limiting methodology is reformulated by transforming the constraints directly onto design variables to produce orthogonal shape modes with equivalent constraints for ensuring smooth and valid iterates. The new generic methodology requires no training data, can be applied to arbitrary topologies using different boundary conditions, and naturally includes translational modes as part of the orthogonal basis. When applied to two standard aerodynamic test cases, the new method has superior performance compared to library-derived modes. Importantly, the optimization convergence rate is independent of the number of design variables, and the optimized objective at high design fidelities is greatly improved by avoiding local minima corresponding to spurious geometries. A nonstandard test case is demonstrated, for which traditional library modes are not useable due to nontrivial topology, and it is shown to benefit from the high-fidelity design space and translational mode made possible with the novel methodology.


    Access

    Check access

    Check availability in my library

    Order at Subito €


    Export, share and cite



    Title :

    Generic Modal Design Variables for Efficient Aerodynamic Optimization



    Published in:

    AIAA Journal ; 61 , 2 ; 739-755


    Publication date :

    2023-02-01




    Type of media :

    Conference paper , Article (Journal)


    Type of material :

    Electronic Resource


    Language :

    English



    Generic Modal Design Variables for Aerodynamic Shape Optimisation

    Kedward, Laurence / Allen, Christian B. / Rendall, T. | AIAA | 2020


    Towards Generic Modal Design Variables for Aerodynamic Shape Optimisation

    Kedward, Laurence / Allen, Christian B. / Rendall, T. | AIAA | 2020


    TOWARDS GENERIC MODAL DESIGN VARIABLES FOR AERODYNAMIC SHAPE OPTIMISATION

    Kedward, Laurence / Allen, Christian B. / Rendall, T. | TIBKAT | 2020


    Efficient Modal Design Variables Applied to Aerodynamic Optimization of a Modern Transport Wing

    Allen, Christian B. / Poole, Daniel J. / Rendall, T. | AIAA | 2016


    Efficient Modal Design Variables Applied to Aerodynamic Optimization of a Modern Transport Wing (AIAA 2016-3215)

    Allen, Christian B. / Poole, Daniel J. / Rendall, T. | British Library Conference Proceedings | 2016