Reduced-Order Aerodynamic Modeling Based on CFD Frequency Responses from Multisine Inputs

Jared A Grauer; Josiah M Waite; Bret K Stanford

NASA NTRS · 20205002345

Reduced-Order Aerodynamic Modeling Based on CFD Frequency Responses from Multisine Inputs

Jared A Grauer·Josiah M Waite·Bret K Stanford

Abstract

A system identification analysis was performed to determine reduced-order models of a computational fluid dynamics (CFD) solver for linear aeroelastic analysis and control design. The application was to the FUN3D code and the flexible half-span wind tunnel test article, in transonic flow conditions, used in the NASA-Boeing collaboration called the Integrated Adaptive Wing Technology Maturation (IAWTM) project. Multiple inputs (structural mode displacements and control surface deflections) were simultaneously excited with orthogonal phase-optimized multisines and multiple outputs (generalized aerodynamic forces) were recorded, from which the matrix of frequency responses were computed using a single CFD run. A state-space model was then fit to the frequency response data using a maximum-likelihood estimator.

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System identification Aeroelasticity Reduced-order model CFD

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BibTeX RIS

Jared A Grauer, Josiah M Waite, Bret K Stanford. Reduced-Order Aerodynamic Modeling Based on CFD Frequency Responses from Multisine Inputs. https://ntrs.nasa.gov/citations/20205002345

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