Elastic Strength of Propellers - An Analysis by Matrix Methods.

Abstract

The determination of displacements and stresses in a propeller blade under the influence of a hydrodynamic pressure load is investigated. Also a simplified approach to the free, undamped vibration of the blade is suggested. The finite element method of analysis is used to analyze the blade as a shell or as a combination of a three dimensional solid and a shell. For the vibration problem, the complete blade was idealized by shell elements only. Constant stress tetrahedra and rectangular prism elements were used for the analysis of the three dimensional solids. A combination of both kinds of elements was found to cause no algorithmic difficulties or inaccuracies in the results and to provide the flexibility to approximate irregular boundaries by the tetrahedron. The stiffness of the shell element was obtained by the superposition of the stiffness of the plane stress element and the fully compatible plate bending element. The results using only the shell element were good both for the static and the dynamic problems. It was felt that with comparable meshes the shell element was more powerful than either of the three dimensional elements. (Author)

Document Details

Document Type
Technical Report
Publication Date
Nov 01, 1970
Accession Number
AD0716463

Entities

People

  • Paris Genalis

Organizations

  • University of Michigan

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Blades
  • Boundaries
  • Displacement
  • Finite Element Analysis
  • Physical Properties
  • Propeller Blades
  • Propellers
  • Resilience
  • Stiffness
  • Three Dimensional
  • Vibration

Fields of Study

  • Engineering

Readers

  • Structural Dynamics.