Similarity Solutions for Partial Differential Equations Generated by Finite and Infinitesimal Groups,

Abstract

The problem of developing systematic methods for obtaining similarity variables is considered for partial differential equations. Similarity variables are a set of transformations which reduce a partial differential equation to an ordinary differential equation. This paper considers two methods of generating similarity variables. The first method uses a group of finite transformations and the second uses a group of infinitesimal transformations. The mathematical theory for both techniques is described and illustrated. The two methods of obtaining similarity variables are applied to the Burgers' equation u(sub y) + u(u sub x) = u sub xx and to the laminar boundary layer equations with a pressure gradient. In all cases considered, new types of similarity variables are found. In addition, the auxiliary conditions are discussed in the light of the new similarity variables obtained for the boundary layer equations. (Author)

Document Details

Document Type
Technical Report
Publication Date
Jul 01, 1971
Accession Number
AD0733497

Entities

People

  • Henry S. Woodard
  • William F. Ames

Organizations

  • University of Iowa

Tags

DTIC Thesaurus Topics

  • Boundaries
  • Boundary Layer
  • Differential Equations
  • Equations
  • Laminar Boundary Layer
  • Layers
  • Mathematics
  • Partial Differential Equations
  • Pressure Gradients

Fields of Study

  • Mathematics

Readers

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