[推荐]Dragonfly Flight III(蜻蜓飞行的升力与需用功率)

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DRAGONFLY FLIGHT
III. LIFT AND POWER REQUIREMENTS
J. M. WAKELING  AND C. P. ELLINGTON
Summary:
A mean lift coefficient quasi-steady analysis has been applied to the free flight of the dragonfly Sympetrum sanguineum and the damselfly Calopteryx splendens. The analysis accommodated the yaw and accelerations involved
in free flight. For any given velocity or resultant aerodynamic force (thrust), the damselfly mean lift coefficient was higher than that for the dragonfly because of its clap and fling. For both species, the maximum mean lift coefficient CL was higher than the steady CL,max. Both species aligned their strokes planes to be nearly normal to the thrust, a strategy that reduces the
CL required for flight and which is different from the previously published
hovering and slow dragonfly flights with stroke planes steeply inclined to the horizontal. Owing to the relatively low costs of accelerating the wing, the aerodynamic power required for flight represents the mechanical power output
from the muscles. The maximum muscle mass-specific power was estimated at 156 and 166Wkg-1 for S.sanguineum and C. splendens, respectively. Measurements
of heat production immediately after flight resulted in mechanical efficiency estimates of 13 % and 9% for S.sanguineum and C. splendens muscles,espectively.