Dynamic testing of thin-walled composite box beams in a vacuum chamberVibration characteristics of thin-walled composite box beams are measured in a rotating environment in a 10-ft diameter vacuum chamber. Symmetric and antisymmetric layup beams are fabricated out of graphite/epoxy prepreg material using an autoclave molding technique. These are excited using piezoelectric ceramic elements and responses are measured using strain gages and accelerometers. First three natural modes are identified using spectrum analyzer over a range of rotational speeds up to 1000 rpm. Measured frequencies and mode shapes (displacement as well as strain) are correlated satisfactorily with calculated finite element results.
Document ID
19900059904
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Chandra, Ramesh (Maryland Univ. College Park, MD, United States)
Chopra, Inderjit (Maryland, University College Park, United States)
Date Acquired
August 14, 2013
Publication Date
January 1, 1989
Subject Category
Structural Mechanics
Meeting Information
Meeting: AHS National Specialists'' Meeting on Rotorcraft Dynamics