Aerodynamic analysis of hummingbird-like hovering flight

Area of Science:

• Aerospace Engineering
• Bio-inspired Robotics
• Fluid Dynamics

Background:

• Flapping wing micro aerial vehicles (FWMAVs) offer advantages over traditional designs for agile flight in confined spaces.
• Hummingbird flight dynamics inspire the development of FWMAVs capable of sustained hovering.
• Existing research focuses on mimicking avian flight for advanced micro aerial vehicle performance.

Purpose of the Study:

• To numerically investigate the impact of flexibility on the aerodynamic performance of flapping wings for FWMAVs.
• To model a hummingbird wing using a membrane and stiffener structure, mimicking insect wing designs.
• To optimize wing design by varying stiffener position and thickness for improved lift and power economy.

Main Methods:

• A fluid-structure interaction (FSI) scheme was employed for numerical simulations.
• The study focused on hovering flight at a Reynolds number of 3000.
• Multiple wing designs were created by altering stiffener placement and thickness, with stiffness comparable to insects.

Main Results:

• Varying stiffener position yielded a maximum average lift coefficient of 0.51.
• Optimizing stiffener thickness increased the average lift coefficient to 0.56.
• The best flexible wing design demonstrated superior performance over rigid counterparts, achieving lift and power economy close to a hummingbird's wing (0.56 CL, 0.88 efficiency vs. 0.61 CL, 1.07 efficiency).

Conclusions:

• Flexible wing design, achieved through strategic stiffener positioning and thickness, is crucial for enhancing FWMAV aerodynamic performance.
• The optimized flexible wing design shows potential for creating efficient, bio-inspired flapping-wing micro aerial vehicles.
• This research provides a pathway for developing manufacturable and high-performing FWMAVs based on natural designs.