Development of K-Version of the Finite Element Method: A Robust Mathematical and Computational Procedure

Abstract

This report summarizes the research carried out under Grant F49620-03-1-0201 on the development of least-squares based finite element models of viscous compressible and incompressible flows as well as shear deformable plates and shells. The main objective of this research was to develop a robust and accurate computational methodology based on least-squares variational principles for the numerical solution of the equations governing plates and shells and viscous incompressible and compressible fluid flows. The use of least-squares principles leads to a variationally unconstrained minimization problem, where compatibility conditions between approximation spaces -such as inf-sup conditions -- never arise. Furthermore, the resulting linear algebraic problem will always have a symmetric positive definite (SPD) coefficient matrix, allowing the use of robust and fast preconditioned conjugate gradient methods for its solution. In this research, the basic theory of least-squares finite element formulations of the equations governing viscous incompressible flows and shear deformable theories of plate and shell structures was carried out and their application through a variety of benchmark problems was illustrated. In the case of fluid flows, penalty least-squares finite element models using high p-levels and low penalty parameters were developed as a good alternative to mixed least-squares finite element models, also developed in the research.

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Document Details

Document Type
Technical Report
Publication Date
Feb 01, 2006
Accession Number
ADA451302

Entities

People

  • Junuthula N. Reddy

Organizations

  • Texas A&M University

Tags

Communities of Interest

  • Air Platforms
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Air Force Research Laboratories
  • Boundary Value Problems
  • Compressible Flow
  • Computational Fluid Dynamics
  • Computational Mechanics
  • Computational Science
  • Differential Equations
  • Equations
  • Finite Element Analysis
  • Fluid Flow
  • Fluid Mechanics
  • Incompressible Flow
  • Mechanical Engineering
  • Mechanics
  • Navier Stokes Equations
  • Partial Differential Equations
  • Scientists

Readers

  • Finite Element Method (FEM) for solving Partial Differential Equations (PDEs)

Technology Areas

  • Space