Static Aeroelastic Analysis with an Inviscid Cartesian Method

Rodriguez, David L.; Aftosmis, Michael J.; Nemec, Marian; Smith, Stephen C.

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NASA NTRS · 20140011551

Static Aeroelastic Analysis with an Inviscid Cartesian Method

Rodriguez, David L.·Aftosmis, Michael J.·Nemec, Marian·Smith, Stephen C.

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Abstract

An embedded-boundary, Cartesian-mesh flow solver is coupled with a three degree-of-freedom structural model to perform static, aeroelastic analysis of complex aircraft geometries. The approach solves a nonlinear, aerostructural system of equations using a loosely-coupled strategy. An open-source, 3-D discrete-geometry engine is utilized to deform a triangulated surface geometry according to the shape predicted by the structural model under the computed aerodynamic loads. The deformation scheme is capable of modeling large deflections and is applicable to the design of modern, very-flexible transport wings. The coupling interface is modular so that aerodynamic or structural analysis methods can be easily swapped or enhanced. After verifying the structural model with comparisons to Euler beam theory, two applications of the analysis method are presented as validation. The first is a relatively stiff, transport wing model which was a subject of a recent workshop on aeroelasticity. The second is a very flexible model recently tested in a low speed wind tunnel. Both cases show that the aeroelastic analysis method produces results in excellent agreement with experimental data.

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BibTeX RIS

Rodriguez, David L., Aftosmis, Michael J., Nemec, Marian, Smith, Stephen C.. 2014-01-13. Static Aeroelastic Analysis with an Inviscid Cartesian Method. https://ntrs.nasa.gov/citations/20140011551

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