Flexural stiffness of feather shafts: geometry rules over material properties
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چکیده
منابع مشابه
Flexural stiffness of feather shafts: geometry rules over material properties.
Flight feathers of birds interact with the flow field during flight. They bend and twist under aerodynamic loads. Two parameters are mainly responsible for flexibility in feathers: the elastic modulus (Young's modulus, E) of the material (keratin) and the geometry of the rachises, more precisely the second moment of area (I). Two independent methods were employed to determine Young's modulus of...
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It is proposed that the kinetic energy of a pigeon's wing, in hovering or slow forward flight, is transferred to the air at the end of the downstroke by a mechanism involving temporary storage of additional energy in bent primary feather shafts. Estimates of the amounts of energy which can be stored and recovered in this way are compared with the requirements of the theory. The hypothesis is no...
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ژورنال
عنوان ژورنال: Journal of Experimental Biology
سال: 2012
ISSN: 1477-9145,0022-0949
DOI: 10.1242/jeb.059451