Aeroelasticity

Aeroelasticity of X-57 like Swept Distributed Propulsion Aircraft Wing

(Courtesy of Image: OpenVSP)

All-electric airplane quieter and more environmentally friendly
High-lift propellers designed to augment lift at low speeds, and turned off and passively fold against nacelles during cruise
Develop a semi-analytical method with Jacobi-Polynomials for aeroelastic analysis of complex airplane configuration with multiple distributed propulsors
The presences of the distributed masses placed in the leading-edge of the wing leading to a larger flutter speed
Extra aerodynamic surfaces by the pods, which cause larger aerodynamic moments about the wing's elastic axis, resulting in a reduced flutter speed.
Divergence speed is lower than flutter speed for a straight uniform wing

Josh Melvin and Wei Zhao, "A Jacobi-Ritz Approach for Flutter Analysis of Swept Distributed Propulsion Aircraft Wing," Proceedings of the ASME 2023 Aerospace Structures, Structural Dynamics, and Materials Conference SSDM2023, June 19-21, 2023, San Diego, California, SSDM 2023-106970

Flutter of Very Thin Plate

Geometric non linearity effect shows a significant effect on the flutter speed of a very thin plate, which helps to increase the bending and torsional stiffness of a very thin plate, resulting in a larger separation between bending and torsion frequencies. Therefore, a higher flutter speed is observed.

(Credit of wind tunnel: Virginia Tech AOE Department)

flutter_test_video_8mps.mp4

Jitish Miglani, Wei Zhao, Siddhant Desai, Varakini Sanmugadas, Joseph A. Schetz, and Rakesh K. Kapania. "Analysis, Design, and Experiments of Metal Flat Plate and Foam Airfoil Flutter Test Articles." In AIAA Scitech 2021 Forum, AIAA-2021-1497. 2021. [Link]

Flight Dynamics and Aeroelasticity of Flexible Wing

The coupling of flight dynamics and aeroelasticity of flexible wing resulting in body freedom flutter. Please see more details in:

Schmidt, D., Zhao, W. and Kapania, R. K., “Flight-Dynamics and Flutter Analyses of a Flying-Wing Research Drone – Invited,” AIAA Atmospheric Flight Mechanics Conference, AIAA SciTech 2016, San Diego, CA, AIAA 2016-1748, DOI: 10.2514/6.2016-1748

Zhao, W., Muthirevula, N., Kapania, R. K., Gupta, A., Regan, D. C. and Seiler, P. J., “A Subcomponent-based Finite Element Model Updating for a Composite Flying-wing Aircraft,” AIAA Atmosphere Flight Mechanics Conference, AIAA SciTech, Grapevine, TX, 2017, AIAA-2017-1393, DOI: 10.2514/6.2017-1393

20889504106_1080p.mp4

Flight test

zaero_bff_femv2p1_side.mp4

Simulation

Nonlinear Aeroelasticity of Truss-braced Wing

Zhao, W., Kapania, R. K., Schetz, J. A., Coggin, J. M., Allen, T. J. and Sexton, B. W. "Nonlinear Aeroelastic Analysis of SUGAR Truss-braced Wing Wind-tunnel Model Under In-plane Loads,'' 56th AIAA/ASME/ASCE/AHS/SC Structures, Structural Dynamics, and Materials Conference. AIAA SciTech 2015, Kissimmee, Florida, AIAA 2015-1173, DOI:10.2514/6.2015-1173

John M. Coggin, Rakesh K. Kapania, Zhao, W., Joseph A. Schetz, V. Hodigere-Siddaramaiah. "Nonlinear Aeroelastic Analysis of a Truss Braced Wing Wind Tunnel Model "55th AIAA/ASMe/ASCE/AHS/SC Structures, Structural Dynamics, and Materials Conference, AIAA SciTech 2014, National Harbor, Maryland, AIAA 2014-0335, DOI: 10.2514/6.2014-0335

Model details of TBW WTM can be found in NASA reports on SUGAR project.

SUGAR TBW WTM Flutter test_Trim.mp4

(Credit: NASA)