Linearized Frequency-Domain Gust Analysis and Adjoint-Based Sensitivities

Kevin E. Jacobson; Andrew S. Thelen; Bret K. Stanford

NASA NTRS · 20230016455

Linearized Frequency-Domain Gust Analysis and Adjoint-Based Sensitivities

Kevin E. Jacobson·Andrew S. Thelen·Bret K. Stanford

Abstract

Gust analysis is added to a linearized frequency-domain method in FUN3D, a NASA computational fluid dynamics solver. The method linearizes about a nonlinear static equilibrium condition and is therefore appropriate for problems with small perturbations such as transonic stochastic gust analysis. In addition to the gust analysis, adjoint-based sensitivities of stochastic gust constraints are implemented for multidisciplinary design optimization. The linearized frequency-domain gust model and adjoint-based sensitivities are described and verified. The method is applied to an optimization for mass minimization of the AGARD 445.6 wing subject to a stochastic gust constraint limiting the displacement of the wing tip.

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Kevin E. Jacobson, Andrew S. Thelen, Bret K. Stanford. Linearized Frequency-Domain Gust Analysis and Adjoint-Based Sensitivities. https://ntrs.nasa.gov/citations/20230016455

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