Author: Renee C. LakePublisher:
ISBN:
Category : Composite materials
Languages : en
Pages : 64
Book Description
Experimental and Analytical Investigation of Dynamic Characteristics of Extension-twist-coupled Composite Tubular Spars
Author: Renee C. LakePublisher:
ISBN:
Category : Composite materials
Languages : en
Pages : 64
Book Description
Experimental and Analytical Investigation of Dynamic Characteristics of Extension-Twist-Coupled Composite Tubular Spars
Author: National Aeronautics and Space Administration (NASA)Publisher: Createspace Independent Publishing Platform
ISBN: 9781722386474
Category :
Languages : en
Pages : 60
Book Description
The results from a study aimed at improving the dynamic and aerodynamic characteristics of composite rotor blades through the use of extension-twist coupling are presented. A set of extension-twist-coupled composite spars was manufactured with four plies of graphite-epoxy cloth prepreg. These spars were noncircular in cross-section design and were therefore subject to warping deformations. Three different cross-sectional geometries were developed: D-shape, square, and flattened ellipse. Three spars of each type were fabricated to assess the degree of repeatability in the manufacturing process of extension-twist-coupled structures. Results from free-free vibration tests of the spars were compared with results from normal modes and frequency analyses of companion shell-finite-element models. Five global modes were identified within the frequency range from 0 to 2000 Hz for each spar. The experimental results for only one D-shape spar could be determined, however, and agreed within 13.8 percent of the analytical results. Frequencies corresponding to the five global modes for the three square spars agreed within 9.5, 11.6, and 8.5 percent of the respective analytical results and for the three elliptical spars agreed within 4.9, 7.7, and 9.6 percent of the respective analytical results. Lake, Renee C. and Izadpanah, Amir P. and Baucom, Robert M. Langley Research Center...
Structural Dynamics Division Research and Technology Accomplishments for FY 1993 and Plans for FY 1994
Author: Eleanor C. WynnePublisher:
ISBN:
Category : Aerodynamics
Languages : en
Pages : 92
Book Description
Thin-Walled Composite Beams
Author: Liviu LibrescuPublisher: Springer Science & Business Media
ISBN: 1402042035
Category : Technology & Engineering
Languages : en
Pages : 627
Book Description
Annotation This is the first monograph devoted to the foundation of the theory of composite anisotropic thin-walled beams and to its applications in various problems involving the aeronautical/aerospace, helicopter, naval and mechanical structures. Throughout the theoretical part, an effort was made to provide the treatment of the subject by using the equations of the 3-D elasticity theory. Non-classical effects such as transverse shear, warping constraint, anisotropy of constituent materials yielding the coupling of twist-bending (lateral), bending (transversal)-extension have been included and their implications have been thoroughly analyzed. Thermal effects have been included and in order to be able to circumvent their deleterious effects, functionally graded materials have been considered in their construction. Implications of the application of the tailoring technique and of the active feedback control on free vibration, dynamic response, instability and aeroelasticity of such structures have been amply investigated. Special care was exercised throughout this work to address and validate the adopted solution methodologies and the obtained results against those available in the literature and obtained via numerical or experimental means.
A Historical Overview of Aeroelasticity Branch and Transonic Dynamics Tunnel Contributions to Rotorcraft Technology and Development
Author: Publisher: DIANE Publishing
ISBN: 1428995803
Category :
Languages : en
Pages : 115
Book Description
Scientific and Technical Aerospace Reports
Author: Monthly Catalogue, United States Public Documents
Author: Publisher:
ISBN:
Category : Government publications
Languages : en
Pages : 1070
Book Description
Monthly Catalog of United States Government Publications
Author: United States. Superintendent of DocumentsPublisher:
ISBN:
Category : Government publications
Languages : en
Pages : 1068
Book Description
February issue includes Appendix entitled Directory of United States Government periodicals and subscription publications; September issue includes List of depository libraries; June and December issues include semiannual index
A Historical Overview of Aeroelasticity Branch and Transonic Dynamics Tunnel Contributions to Rotorcraft Technology and Development
Author: Aeronautical Engineering
Author: Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 932
Book Description
A selection of annotated references to unclassified reports and journal articles that were introduced into the NASA scientific and technical information system and announced in Scientific and technical aerospace reports (STAR) and International aerospace abstracts (IAA).