Three-Dimensional Uncoupled Fluid Structure Analysis of Small Unmanned Aerial Vehicle Wing

Abstract

Analyzing the interaction between a fluid and an exposed structure is vital in the design of numerous applications, including the optimization of aerodynamic bodies such as the flexible wings of small unmanned aerial vehicles. Various techniques currently exist to study such fluid/structure interactions, including experimental approaches and numerical techniques that couple fluid and structural analysis tools. In this study, a novel uncoupled static aeroelastic analysis method is demonstrated for determination of the aeroelastic response of three-dimensional wings for the first time. The results indicate that this uncoupled static aeroelastic analysis method is capable of accurately predicting the pressure and displacement fields of a flexible wing, exhibiting at most a 2% error relative to traditional coupled aeroelastic analysis results and a 2.3% error relative to experimental results. Additionally, because the fluid and structural solvers are uncoupled, it is herein demonstrated that the uncoupled static aeroelastic analysis method is capable of reusing a single computationally expensive fluid data set to evaluate multiple internal wing structural configurations across a range of angles of attack while maintaining similar levels of accuracy, thereby reducing the total computational expense by as much as 70%. Furthermore, it is also demonstrated that the uncoupled static aeroelastic analysis method is suitable for preliminary design optimization of the internal structure of wings, which may experience either simple (bending only) or complex (bending and twisting) deformation.