SR18  Métodos Experimentais em Termofluidodinâmica    Titulo: DETERMINAÇÃO DA DIFUSIDADE TÉRMICA E DA CONDUTIVIDADE TÉRMICA DE MATERIAIS METÁLICOS UTILIZANDO TÉCNICAS DE OTIMIZAÇÃO   Resumo : THERMAL CONDUCTIVITY AND DIFFUSIVITY ESTIMATION OF METALIC MATERIALS USING OPTIMIZATION TECHNIQUES ABSTRACT. THIS PAPER DESCRIBES AN EXPERIMENTAL TECHNIQUE TO DETERMINE SIMULTANEOUSLY THE THERMAL DIFFUSIVITY, , AND THERMAL CONDUCTIVITY, , OF A STAINLESS STEEL AISI 304 MODIFIED SAMPLE. AN ONE-DIMENSIONAL THERMAL MODEL IS USED. A HEAT FLUX HISTORY IS IMPOSED AT THE FRONTAL SURFACE OF THE SAMPLE WHILE THE OTHER SURFACE IS ISOLATED. THE HEAT FLUX AND TEMPERATURE ARE RESPECTIVELY MEASURED AT THE FRONTAL HEATING SURFACE AND AT THE REAR SURFACE. THERMAL PROPERTIES  AND  ARE ESTIMATED BY USING UNCONSTRAINED OPTIMIZATION TECHNIQUES IN A MINIMUM SQUARE ERROR FUNCTION BETWEEN THE EXPERIMENTAL AND ESTIMATED TEMPERATURE. THREE UNCONSTRAINED ALGORITHMS OF OPTIMIZATION ARE USED TO CALCULATE THE SEARCH DIRECTION. IN EACH CASE THE UNIDIRECTIONAL SEARCH GOLDEN SECTION TECHNIQUE FOLLOWED BY A POLYNOMIAL APPROXIMATION ARE USED IN ORDER TO REACH MORE CONFIDENCE AND PRECISION. KEY-WORDS: PARAMETER ESTIMATION, THERMAL PROPERTIES MEASUREMENTS, HEAT CONDUCTION, INVERSE PROBLEM, OPTIMIZATION.     Autores : Guimaraes, Gilmar 0 Gutts, Saulo 0 Laurent, Michel 0 Lima e Silva, Sandro Metrevelle Marcondes     Trabalho Completo :   COBEM99 | Comissão  Organizadora | Palestras | Sessões Técnicas | Autor | Simpósios e Sessões Especiais | Revisores |  Título  dos  Trabalhos | Local