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dc.contributor.advisorWoods, E. Roberts
dc.contributor.authorCouch, Mark A.
dc.dateJune 2003
dc.date.accessioned2012-08-22T15:30:23Z
dc.date.available2012-08-22T15:30:23Z
dc.date.issued2003-06
dc.identifier.urihttp://hdl.handle.net/10945/9855
dc.descriptionApproved for public release; distribution is unlimiteden_US
dc.description.abstractThis dissertation develops the equations of motion for the structural and aerodynamic forces and moments of a rotor blade with a trailing-edge flap using eight degrees of freedom. Lagrange's equation is applied using normal modes to find the flutter frequency and speed similar to the classic fixed-wing method developed by Smilg and Wasserman. However, rotary-wing concerns are addressed including different freestream velocities along the blade (variation of reduced frequency along the span of the rotor blade) and the influence of previously shed vortices on the aerodynamic forces and moments (Loewy's returning wake). While Loewy [Ref. 49] did not explicitly state that his 2-D theory would apply to rotor blades with trailing-edge flaps, the manner in which the theory was developed allows it to be applied in this manner. Comparisons to classic 1DOF, 2DOF and 3DOF flutter theories are made to validate this theory in the limiting cases. Flutter analyses, including g-. plots, of an example rotor blade with five degrees of freedom are performed for various rigid body flap frequencies. Classic methods of rotor blade design of ensuring freedom from flutter are to collocate the center of gravity (c.g.), elastic axis (e.a.), and aerodynamic center (a.c) at the 25% chord. With the development of rotor blades with trailing-edge flaps, it is shown that this current design practice is not valid when a trailing-edge flap is incorporated.en_US
dc.format.extentxxii, 213 p. : ill. (some col.) ; 28 cm.en_US
dc.publisherMonterey, California. Naval Postgraduate Schoolen_US
dc.rightsThis publication is a work of the U.S. Government as defined in Title 17, United States Code, Section 101. As such, it is in the public domain, and under the provisions of Title 17, United States Code, Section 105, may not be copyrighted.en_US
dc.subject.lcshUnsteady flow (Aerodynamics)en_US
dc.titleA three-dimensional flutter theory for rotor blades with trailing-edge flapsen_US
dc.contributor.departmentAeronautics and Astronautics
dc.subject.authorFlutteren_US
dc.subject.authorRotary Wingen_US
dc.subject.authorAeroelasticity. Trailing-edge Flapsen_US
dc.subject.authorUnsteady Aerodynamicsen_US
dc.subject.authorStructural Dynamicsen_US
dc.subject.authorHolzer Methoden_US
dc.subject.authorMyklestad-Prohl Methoden_US
dc.subject.authorRotor Bladesen_US
dc.subject.authorVibrations;en_US
dc.description.serviceCommander, United States Navyen_US
etd.thesisdegree.namePh.D in Aeronautical and Astronautical Engineeringen_US
etd.thesisdegree.levelDoctoralen_US
etd.thesisdegree.disciplineAeronautical and Astronautical Engineeringen_US
etd.thesisdegree.grantorNaval Postgraduate School (U.S.)en_US


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