Aerodynamic Performance of a Nanostructure-Induced Multistable Shell

Shenghui Yi,Jian Lu,Xiaoqiao He,Lu Shen,Chih-Yung Wen

doi:10.3390/aerospace8110350

Abstract

Multistable shells that have the ability to hold more than one stable configuration are promising for adaptive structures, especially for airfoil. In contrast to existing studies on bistable shells, which are well demonstrated by the Venus flytrap plant with the ability to feed itself, this work experimentally studies the aerodynamic response of various stable configurations of a nanostructure-induced multistable shell. This multistable shell is manufactured by using nanotechnology and surface mechanical attrition treatment (SMAT) to locally process nine circular zones in an original flat plate. The aerodynamic responses of eight stable configurations of the developed multistable shell, including four twisted configurations and four untwisted configurations with different cambers, are visually captured and quantitively measured in a wind tunnel. The results clearly demonstrate the feasibility of utilizing different controllable configurations to adjust the aerodynamic performance of the multistable shell.

Highlights

Morphing structures are very promising in engineering fields, especially in the aerodynamic domain, to provide multiple configurations and realize various functions using one structure
With the ability of holding more than one stable configuration by their own mechanical properties, multistable shells provide an ideal solution for morphing structures without requiring external supports or consuming input energies continuously, which are demonstrated by the Venus flytrap plant that has the ability to feed itself in nature [11]
The shape adaptation can be realized by using smart material with a finite energy [12,13,14,15,16,17], which transforms a synthetic multistable shell from one stable configuration into another stable one, providing a significant advantage over morphing structures that rely on inputting energies continuously to maintain deformations

Summary

Introduction

Morphing structures are very promising in engineering fields, especially in the aerodynamic domain, to provide multiple configurations and realize various functions using one structure. With the ability of holding more than one stable configuration by their own mechanical properties, multistable shells provide an ideal solution for morphing structures without requiring external supports or consuming input energies continuously, which are demonstrated by the Venus flytrap plant that has the ability to feed itself in nature [11]. The shape adaptation can be realized by using smart material with a finite energy [12,13,14,15,16,17], which transforms a synthetic multistable shell from one stable configuration into another stable one, providing a significant advantage over morphing structures that rely on inputting energies continuously to maintain deformations. No report has been found on aerodynamic behaviors of multistable shells that could hold more than two stable configurations

Methods

Results

Conclusion