A simple model of wake capture aerodynamics.

Area of Science:

• Aerodynamics
• Bio-inspired engineering
• Fluid mechanics

Background:

• Flapping wings interact with their own wake, influencing aerodynamic forces.
• Existing quasi-steady models for insect flight often neglect these wake capture effects.

Purpose of the Study:

• To develop a simple method for incorporating wake capture effects into analytical quasi-steady models.
• To improve the prediction of aerodynamic forces in hovering insect flight.

Main Methods:

• Modeled the local wake flow field as an additional induced velocity component.
• Integrated this component into existing quasi-steady models, switching it in at each half-stroke.
• Compared model predictions with experimental data for eight test cases.

Main Results:

• The model showed satisfactory agreement with experimental data for lift and drag variations.
• Sensitivity analysis revealed that the wing's translational velocity profile significantly impacts wake capture forces.
• High translational velocity profiles up to stroke reversal resulted in larger wake capture effects compared to sinusoidal profiles.

Conclusions:

• The developed approach effectively predicts wake capture effects in insect flight.
• Translational velocity profiles significantly influence aerodynamic forces, with implications for natural and engineered flapping flight.
• High accelerations near stroke reversal, while enhancing wake capture, are mechanically costly and impractical.