Experimental Spin Testing of Integrally Damped Composite Plates

Experimental Spin Testing of Integrally Damped Composite Plates
Author: National Aeronautics and Space Administration (NASA)
Publisher: Createspace Independent Publishing Platform
Total Pages: 34
Release: 2018-07-02
Genre:
ISBN: 9781722220266

The experimental behavior of spinning laminated composite pretwisted plates (turbo-fan blade-like) with small (less than 10% by volume) integral viscoelastic damping patches was investigated at NASA-Lewis Research Center. Ten different plate sets were experimentally spin tested and the resulting data was analyzed. The first-four plate sets investigated tailoring patch locations and definitions to damp specific modes on spinning flat graphite/epoxy plates as a function of rotational speed. The remaining six plate sets investigated damping patch size and location on specific modes of pretwisted (30 degrees) graphite/epoxy plates. The results reveal that: (1) significant amount of damping can be added using a small amount of damping material, (2) the damped plates experienced no failures up to the tested 28,000 g's and 750,000 cycles, (3) centrifugal loads caused an increase in bending frequencies and corresponding reductions in bending damping levels that are proportional to the bending stiffness increase, and (4) the centrifugal loads caused a decrease in torsion natural frequency and increase in damping levels of pretwisted composite plates. Kosmatka, John Glenn Research Center NCC3-493...

Scientific and Technical Aerospace Reports

Scientific and Technical Aerospace Reports
Author:
Publisher:
Total Pages: 602
Release: 1995
Genre: Aeronautics
ISBN:

Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.

NASA SP.

NASA SP.
Author:
Publisher:
Total Pages: 654
Release: 1992
Genre: Aeronautics
ISBN:

Low-Speed Wind Tunnel Testing

Low-Speed Wind Tunnel Testing
Author: Jewel B. Barlow
Publisher: John Wiley & Sons
Total Pages: 738
Release: 1999-02-22
Genre: Technology & Engineering
ISBN: 0471557749

A brand-new edition of the classic guide on low-speed wind tunnel testing While great advances in theoretical and computational methods have been made in recent years, low-speed wind tunnel testing remains essential for obtaining the full range of data needed to guide detailed design decisions for many practical engineering problems. This long-awaited Third Edition of William H. Rae, Jr.'s landmark reference brings together essential information on all aspects of low-speed wind tunnel design, analysis, testing, and instrumentation in one easy-to-use resource. Written by authors who are among the most respected wind tunnel engineers in the world, this edition has been updated to address current topics and applications, and includes coverage of digital electronics, new instrumentation, video and photographic methods, pressure-sensitive paint, and liquid crystal-based measurement methods. The book is organized for quick access to topics of interest, and examines basic test techniques and objectives of modeling and testing aircraft designs in low-speed wind tunnels, as well as applications to fluid motion analysis, automobiles, marine vessels, buildings, bridges, and other structures subject to wind loading. Supplemented with real-world examples throughout, Low-Speed Wind Tunnel Testing, Third Edition is an indispensable resource for aerospace engineering students and professionals, engineers and researchers in the automotive industries, wind tunnel designers, architects, and others who need to get the most from low-speed wind tunnel technology and experiments in their work.