以數值模擬探討昆蟲懸停振翅產生升力的關鍵機制

本文主要以數值模擬探討翅膀彈性與旋轉效應對撲翼飛行（flapping-wing flight）之氣動力學的影響。為簡化問題，本研究將流場運動方程式設成二維；再者，由於昆蟲翅膀的厚度可忽略，因此對於二維流場而言昆蟲翅膀可視為一具有彈性的線段。本文利用二維渦流板格法（vortex panel method）求解非穩態流場。為了考量昆蟲翅膀於拍翅時所呈現的大變形姿態，本研究以樑的幾何非線性方程式（geometrically nonlinear equation for bending beams）來模擬昆蟲翅膀的變形，並以適當的演算法進行迭代來求得流固耦合（fluid-structure interaction）模式下的數值解。本研究證實適度的翅膀撓性剛度及翅膀旋轉角速度可有效利用渦流對捕捉效應（vortex-pair capture effect）來提高升力。

關鍵字

渦流板格法；翅膀撓性剛度；翅膀旋轉；渦流對捕捉

並列摘要

In this study, we examine numerically the effect of wing flexibility and wing rotation on the aerodynamic performance of flapping flight. In the present work, a two dimensional computational study of hovering flight by single flapping wing is considered. In the 2-D framework, the wing is treated as an elastic filament. Based on the underlying linear potential flow theory, the principle of aerodynamic superposition is used to deal with the complex aerodynamic configuration. A potential flow 2-D vortex panel method is employed to solve the unsteady hydrodynamic problem of a flapping wing. To account for the large deformation nature of the wing, motion of the filament is modeled by a geometrically nonlinear equation for bending beams. In this paper, we use a proper iterative numerical algorithm to deal with the fluid-structure interaction problem. Present study suggests that the moderate wing flexibility and wing rotation speed can benefit from the vortex-pair capture effect.

並列關鍵字

vortex panel method ； wing flexibility ； wing rotation ； vortex-pair capture

主題瀏覽