# Study on Fluid–Structure Interaction of a Camber Morphing Wing

^{*}

## Abstract

**:**

## 1. Introduction

## 2. Model Definition and Morphing Structures

## 3. Test and Numerical Methods

#### 3.1. Facilities

#### 3.2. Numerical Methods

#### 3.2.1. CFD Model

^{+}< 1.

#### 3.2.2. Structural Motion Calculation

#### 3.2.3. Fluid–Structure Interaction Mode

#### 3.2.4. Data Exchange between Different Physical Fields

_{i}(x

_{i},y

_{i}). The plate satisfies the static equilibrium equation, in which D is the elastic coefficient of the plate and q is the load distribution of the plate. It is assumed that the solution of the equation is as follows:

^{5}, and the computation domain size is 1200 (circumferential) × 140 (radial), totalling 168,000 grid nodes.

^{6}, and 0.032° angle of attack. The results of the trailing edge and the lower wing surface match each other well. There are certain differences between the results near the leading edge and the shock wave region. It should be noted that this set of grids is suitable for Reynolds numbers above one million, and the wall grid y+ is in the range of 0.7~1.1. However, the experimental Reynolds number in the literature is above ten million, which leads to a larger wall grid y+ ranging from 7 to 14. Therefore, the difference between the results is understandable. The results showed that the grid quality was good enough to meet the requirements of this research.

## 4. Results

#### 4.1. Comparison of CFD Results with Test Results

#### 4.2. Effect of Wing Deformation on Flow Structure

#### 4.3. Deformation’s Impact on Aerodynamic Characteristics

## 5. Conclusions

## Author Contributions

## Funding

## Data Availability Statement

## Conflicts of Interest

## Nomenclature

${c}_{p}$ | Isobaric specific heat |

ρ_{∞} | Incoming flow density |

u_{∞} | Incoming flow velocity |

T | Incoming flow turbulence |

μ_{l} | Laminar viscosity coefficient of the incoming flow |

ρ_{1}, d_{1} | Density of the first layer of the grid center near the object surface and the distance to the model surface |

$\left\{w\left(x,y,z,t\right)\right\}$ | Structural deformation vector of the model surface |

$\left\{F\left(t\right)\right\}$, $\left\{q\left(t\right)\right\}$ | Generalized displacement and the generalized aerodynamic force, respectively |

$\left[M\right]$, $\left[D\right]$, $\left[K\right]$ | Generalized mass, damping, and stiffness matrices of the structure |

$\left\{F\left(t\right)\right\}$ | Generalized aerodynamics, which link the structure with aerodynamics |

Fs, Fa | Structural point force vector and aerodynamic force vector, respectively |

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**MDPI and ACS Style**

Wang, Y.; Lei, P.; Lv, B.; Li, Y.; Guo, H.
Study on Fluid–Structure Interaction of a Camber Morphing Wing. *Vibration* **2023**, *6*, 1060-1074.
https://doi.org/10.3390/vibration6040062

**AMA Style**

Wang Y, Lei P, Lv B, Li Y, Guo H.
Study on Fluid–Structure Interaction of a Camber Morphing Wing. *Vibration*. 2023; 6(4):1060-1074.
https://doi.org/10.3390/vibration6040062

**Chicago/Turabian Style**

Wang, Yuanjing, Pengxuan Lei, Binbin Lv, Yuchen Li, and Hongtao Guo.
2023. "Study on Fluid–Structure Interaction of a Camber Morphing Wing" *Vibration* 6, no. 4: 1060-1074.
https://doi.org/10.3390/vibration6040062