Publication Date
2012
Document Type
Thesis
Committee Members
Haibo Dong (Advisor), George Huang (Other), Hui Wan (Committee Member), Zifeng Yang (Committee Member)
Degree Name
Master of Science in Engineering (MSEgr)
Abstract
A simplified conceptual flapping wing MAV design, capable of hover, is formed from the works of both biologists and engineers, studying the behavior of flying insects and the aerodynamics of flapping flight. With this new model, hovering hinged plates are used to study the effects of passive deflection on aerodynamic performance using two-dimensional Direct Numerical Simulations (DNS) at low Reynolds numbers (Re). The hinge is modeled as a torsional spring at the leading edge, where prescribed motion is applied. The influence of forced-to-natural frequency ratio (hinge stiffness) and stroke-to-chord ratio (leading edge kinematics) are studied, to explore the effects that either has on aerodynamic performance. Parameters are chosen from inspiration given by both insects and birds. The influences of leading edge kinematics give rise to the notion that performance improves with stroke amplitude across hinges of all stiffness. Hinge stiffness is determined to drastically affect the angle of attack at midstroke at small stroke amplitudes, as well as the behavior at stroke reversal for all kinematics. By tailoring the leading edge kinematics and the hinge stiffness, the angle of attack through the stroke and pitch rate at stroke reversal can be adjusted to promote the wake capture mechanism, and to form a stronger downwash, effectively improving the aerodynamic performance of the flapping plate. The results of this study are used to suggest a set of parameters that would be favorable for use in the conceptual hovering MAV design.
Page Count
69
Department or Program
Department of Mechanical and Materials Engineering
Year Degree Awarded
2012
Copyright
Copyright 2012, all rights reserved. This open access ETD is published by Wright State University and OhioLINK.
