Accession Number : ADA306242

Title :   Theoretical Analysis of Impact in Composite Plates.

Descriptive Note : Contract rept.,

Corporate Author : PRINCETON UNIV NJ DEPT OF AEROSPACE AND MECHANICAL SCIENCES

Personal Author(s) : Moon, F. C.

PDF Url : ADA306242

Report Date : 1972

Pagination or Media Count : 102

Abstract : The calculated stresses and displacements induced in anisotropic plates by short duration impact forces are presented in this report. The theoretical model attempts to model the response of fiber composite turbine fan blades to impact by foreign objects such as stones and hail-stones. In this model the determination of the impact force uses the Hertz impact theory. The plate response treats the laminated blade as an equivalent anisotropic material using a form of Mindlin's theory for crystal plates. The analysis makes use of a computational tool called the 'fast Fourier transform'. Results are presented in the form of stress contour plots in the plane of the plate for various times after impact. Examination of the maximum stresses due to impact versus ply layup angle reveals that the + or - 15 deg layup angle gives lower flexural stresses than 0 deg, + or - 30 deg and + or - 45 deg cases. (MM)

Descriptors :   *LAMINATES, *FIBER REINFORCED COMPOSITES, *IMPACT STRENGTH, *GAS TURBINE BLADES, *GRAPHITE EPOXY COMPOSITES, MATHEMATICAL MODELS, EQUATIONS OF MOTION, STRESS ANALYSIS, DISPLACEMENT, COMPOSITE STRUCTURES, FAN BLADES, JET ENGINES, PLATES, ANISOTROPY, HAIL, BIRD STRIKES, FAST FOURIER TRANSFORMS, FLEXURAL PROPERTIES.

Subject Categories : Laminates and Composite Materials
      Jet and Gas Turbine Engines

Distribution Statement : APPROVED FOR PUBLIC RELEASE