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Aerodynamic optimization of a two-segment flapping wing via kinematic timing design
1School of Transportation Science and Engineering, CAUC, Tianjin 300300, People's Republic of China.
Bioinspiration & Biomimetics
|April 20, 2026
Summary
Introducing a dwell phase in flapping-wing aircraft design significantly reduces negative lift during transitions. This albatross-inspired approach enhances aerodynamic stability and energy efficiency for practical applications.
Area of Science:
- Aerospace Engineering
- Fluid Dynamics
- Bio-inspired Robotics
Background:
- Flapping-wing aircraft face challenges with negative-lift excursions during stroke transitions.
- These excursions negatively impact aerodynamic stability and energy efficiency, limiting practical use.
Purpose of the Study:
- To investigate an albatross-inspired two-segment flapping-wing configuration.
- To explore the use of a dwell phase at stroke reversal as a kinematic timing strategy.
- To analyze the effects of dwell timing on aerodynamic loads and vortex structures.
Main Methods:
- Development of a three-phase kinematic model (upstroke-dwell-downstroke).
- Simulation using the XFlow lattice Boltzmann solver.
- Numerical analysis at flapping frequencies of 3-5 Hz with varied dwell-time ratios.
Main Results:
- Incorporating a dwell phase effectively reduced negative-lift fluctuations.
- Peak negative lift decreased with increasing dwell-time ratio up to 1/6 of the cycle.
- A dwell-time ratio of 1/6 reduced peak negative lift by approximately 37% without inducing oscillations.
Conclusions:
- A dwell phase in flapping-wing kinematics is a viable strategy for improving aerodynamic performance.
- Optimal dwell timing, around 1/6 of the cycle, significantly mitigates negative lift.
- This research offers quantitative guidance for motion sequencing and aerodynamic optimization in multi-segment flapping-wing systems.
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