Accession Number : ADA194917

Title :   Boundary Shape Identification Problems in Two-Dimensional Domains Related to Thermal Testing of Materials.

Descriptive Note : Contractor rept.,

Corporate Author : INSTITUTE FOR COMPUTER APPLICATIONS IN SCIENCE AND ENGINEERING HAMPTON VA

Personal Author(s) : Banks, H T ; Kojima, Fumio

PDF Url : ADA194917

Report Date : Mar 1988

Pagination or Media Count : 33

Abstract : Domain identification problems are important in the design of engineering systems and frequently such problems are treated as a branch of the calculus of variations which involves nonlinear optimization techniques, optimal control theory, partial differential equations (elliptic, parabolic, hyperbolic, etc.) and related numerical methods. Domain identification for elliptic systems has been studied theoretically and numerically by many others. For parabolic systems, a couple of numerical methods for identifying the domain or boundary have been investigated. In this paper, our concern for domain identification is motivated by an application that is different from these shape design problems. However, as we shall see, the resulting theoretical aspects are closely related. Recently, associated with the use of fiber reinforced composite materials for aerospace structures, there is growing interest in the detection and characterization of large structural flaws which may not be detectable by visual inspection. One recent effort has focused on non-destructive evaluation methods (NDE) based on the measurement of thermal diffusivity in composite materials. Motivated by these problems, we consider the domain identification for parabolic systems.

Descriptors :   *AEROSPACE CRAFT, *BOUNDARY VALUE PROBLEMS, *COMPOSITE MATERIALS, *FIBER REINFORCED COMPOSITES, *FIBER REINFORCEMENT, CALCULUS OF VARIATIONS, CONTROL THEORY, DETECTION, DIFFUSIVITY, DOMAIN WALLS, ELLIPSES, ENGINEERING, IDENTIFICATION, MATERIALS, NONDESTRUCTIVE TESTING, NONLINEAR SYSTEMS, NUMERICAL METHODS AND PROCEDURES, OPTIMIZATION, PARABOLAS, PARTIAL DIFFERENTIAL EQUATIONS, PROBLEM SOLVING, SHAPE, STRUCTURAL PROPERTIES, TEST AND EVALUATION, THERMAL PROPERTIES, TWO DIMENSIONAL, VISUAL INSPECTION

Subject Categories : Laminates and Composite Materials

Distribution Statement : APPROVED FOR PUBLIC RELEASE