Numerical methods for aerodynamically coupled thin structures

Abstract

Potential solvers represent an effective tool for the aeronautical engineer both in terms of helping the undergraduate engineer grapple with fluid mechanics, as well as the graduate engineer during the design spiral of an aircraft. However, their usage is not solely limited to aerodynamics, but can also be applied to structures to begin giving a preliminary aeroelastic analysis. In the context of a pair of plates coupled solely by aerodynamics, a potential-based solver is of interest to determine the fluid-structure interaction (FSI) when compared to the time and computationally expensive transient Computational Fluid Dynamics (CFD) simulation. It is with this in mind that the groundwork towards such a potential model has been developed within this dissertation. Three core models have been developed to approach the problem of these aerodynamically coupled plates. They are: an unsteady frequency-based Vortex Lattice Method (fVLM), an inextensible plate (IP) structural model for large deflections coupled to an fVLM for aeroelastic response, and a coupled ONERA-EDLIN (ONERA-C) dynamic stall model with vortex core implementation. The goal model is a combination of all the above models to produce a transient aeroelastic model with dynamic stall corrected (via ONERA) VLM aerodynamics, and a large deflection structural model (via IP). This model is titled as Frequency-based nonLinear Aerodynamics for Plate-Plate Interactions Based On Inextensibility (FLAPPI-BOI). Validation of these models was performed with a physical analogue of the plates within the 3 ft x 4 ft wind tunnel at the University of Sydney. Deflections were tracked by photogrammetry using an OptiTrack camera system feeding directly into MATLAB via a modified API to Motive. Based upon the intention of this research to act as a springboard for future development of potential models, and to develop the initial framework for an advanced potential-based aeroelastic solver, this intention was met.