Random-Vibration Analysis System for Complex Structures. Part 1: Engineering User's Guide

Abstract

A user's guide is presented for a computer program developed to aid in the design of sonic-fatigue-resistant aircraft structure. The program employs matrix methods to calculate statistical measurements of response (deflection and stress) for complex structure subjected to pressure loads random in both time and space. The program is in two phases. Finite-element methods are used in the first phase to determine structural characteristics such as flexibility, natural frequencies, and modes of vibration. In the second phase, a cross-power spectral density loading function, is generated and combined with structural characteristics to compute response. Either cross power spectral density or joint statistical moments, including second spectral moments useful in fatigue analysis, can be computed for response. The loading function models a decayed progressive wave typical of laboratory noise sources. Different loading functions can be supplied by the user, because the program is constructed in modular form. The program was written for the IBM 7094 computer primarily in FORTRAN IV language with a MAP language matrix manipulation module.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Nov 01, 1968
Accession Number
AD0845604

Entities

People

  • D. R. Lagerquist
  • L. D. Jacobs

Organizations

  • Boeing Commercial Airplanes

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Air Force
  • Buildings And Structures
  • Computer Programs
  • Computers
  • Dynamic Response
  • Finite Element Analysis
  • Frequency
  • Frequency Shift
  • Language
  • Measurement
  • Random Vibration
  • Resonant Frequency
  • Sonic Fatigue
  • Vibration
  • Waves

Fields of Study

  • Physics

Readers

  • Computer Science.
  • Statistical inference.
  • Structural Dynamics.

Technology Areas

  • Space