Developing tools for assessing the fluid structure interaction of passive adaptive composite foils

Abstract

The study presents an experimental and numerical evaluation of bend-twist elastic coupling in composite passive-adaptive structures. Due to the lack of experimental validation in Fluid Structure Interaction (FSI) investigations, a full-field deformation of an aerofoil-shaped section under wind loading is measured. The experimental analysis is carried out at the University of Southampton 3.5 m × 2.4 m R. J. Mitchell wind tunnel using full-field non-contact measurement techniques such as high speed three dimensional Digital Image Correlation (DIC) and stereoscopic Particle Image Velocimetry (PIV). After assessing the validity and repeatability of the experiments, the study focuses on the development of a numerical FSI investigation that involves the use of a structural and a fluid solver to simulate the aero-elastic behaviour of composite tailored structures with different lay-up arrangements. The numerical analysis is developed as a design tool to allow the structure investigated to maximise bend-twist coupling under increased aerodynamic loading.

Toward the development of a hydrofoil tailored to passively reduce its lift response to fluid load

“…Moreover, the aerofoil with the internal Carbon-Glass spar presents a higher C L /C D meaning that the reduction in induced drag has more impact than the reduction in lift due to deflection. A comparison of a PAC model with a quasi-isotropic structure of a similar aerofoil was presented in (Marimon Giovannetti et al, 2016). From Figure 14 it is possible to see that the ratio of tip deflection between a quasi-isotropic and a PAC for a range of angles of attack and wind speeds varies non-linearly.…”

End-to-end efficiency quantification of an autonomous underwater vehicle propulsion system

“…It has been reported that accurate predictions of flow past flexible wings and propellers can be made by carrying out fluid-structure interaction simulations which solve for both structural response and fluid loading simultaneously (Giovannetti et al, 2016(Giovannetti et al, , 2018Maljaars et al, 2018). However, such simulations were beyond the scope of the current investigation and would also require reliable validation data for rotating geometries, which have proven difficult to obtain.…”

Dynamic Fluid Structure Interaction of NACRA 17 Foil

“…It is common to use a Finite Element Model (FEM) to solve the solid problem. The complexity of the models varies from simple beam elements [1,3,5,7,[9][10][11][12] to the more complex shell [6][7][8][9] and solid elements [2] and in some cases even considering anisotropic material properties. The fluid flow problem can also be solved with varying degrees of complexity from lifting line method [3,12] to unsteady Reynolds Average Navier-Stokes (RANS) Finite Volume Methods (FVM) [6].…”

“…More details on fluid flow models for foils can be found in [14]. Some studies [2,7,9] found bend-twist coupling of the foils to be important. Experience with large flow induced deformation of thin structures can also be found on the aerodynamic of sailing boats, where recent work [15][16][17][18][19] investigated FSI simulation of yacht sails.…”

“…Modern hydrofoils are thin to reduce drag and the tin structure results in large deformations during sailing and therefore Fluid Structure Interaction (FSI) are important. In recent years much work has been published on FSI of foils, see for example [1][2][3][4][5][6][7][8][9][10][11][12].…”