Data analysis methods for flash thermal diffusivity experiments

Sweet, J. N.

doi:10.2172/6312039

Title: Data analysis methods for flash thermal diffusivity experiments

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Abstract

New methods, based on nonlinear least squares techniques, are presented for reducing flash diffusivity data obtained on layered composite samples. Analytical solutions to the transient heat conduction equation are derived by the Laplace transform technique for the cases of two and three layer samples with interfacial thermal resistance between the layers and thermal losses at the external boundaries. The use of the analytical solutions in least squares fitting programs is then discussed, with emphasis on the two layer problem. A description of FORTRAN computer programs which implement the calculations is given, with emphasis on the non-linear least squares fitting routine LSTSQRSL3. This program can determine the external boundary thermal loss factor and either the thermal diffusivity of one of the layers or the interfacial resistance between the layers. Two examples of the use of this program are given. In the first, the thermal diffusivity of an alumina layer in a graphite-alumina sample is determined, and in the second, the diffusivity of an enamel paint on a stainless steel substrate is determined. 34 refs., 12 figs., 2 tabs.

Authors:: Sweet, J. N.

Publication Date:: Wed Feb 01 00:00:00 EST 1989

Research Org.:: Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

OSTI Identifier:: 6312039

Report Number(s):: SAND-89-0260
ON: DE89010274

DOE Contract Number:: AC04-76DP00789

Resource Type:: Technical Report

Resource Relation:: Other Information: Portions of this document are illegible in microfiche products

Country of Publication:: United States

Language:: English

Subject:: 99 GENERAL AND MISCELLANEOUS//MATHEMATICS, COMPUTING, AND INFORMATION SCIENCE; 42 ENGINEERING; THERMAL DIFFUSIVITY; DATA ANALYSIS; ALUMINIUM OXIDES; COMPUTERIZED SIMULATION; D CODES; F CODES; FORTRAN; L CODES; LAYERS; LEAST SQUARE FIT; MATHEMATICAL MODELS; ALUMINIUM COMPOUNDS; CHALCOGENIDES; COMPUTER CODES; MAXIMUM-LIKELIHOOD FIT; NUMERICAL SOLUTION; OXIDES; OXYGEN COMPOUNDS; PHYSICAL PROPERTIES; PROGRAMMING LANGUAGES; SIMULATION; THERMODYNAMIC PROPERTIES; 990230* - Mathematics & Mathematical Models- (1987-1989); 990220 - Computers, Computerized Models, & Computer Programs- (1987-1989); 420400 - Engineering- Heat Transfer & Fluid Flow

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                    Sweet, J. N. Data analysis methods for flash thermal diffusivity experiments.  United States: N. p., 1989. 
        Web.  doi:10.2172/6312039.

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                    Sweet, J. N. Data analysis methods for flash thermal diffusivity experiments.  United States.  https://doi.org/10.2172/6312039

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                    Sweet, J. N. 1989.  
        "Data analysis methods for flash thermal diffusivity experiments".  United States.  https://doi.org/10.2172/6312039.  https://www.osti.gov/servlets/purl/6312039.

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@article{osti_6312039,

  title        = {Data analysis methods for flash thermal diffusivity experiments},

  author       = {Sweet, J. N.},

  abstractNote = {New methods, based on nonlinear least squares techniques, are presented for reducing flash diffusivity data obtained on layered composite samples. Analytical solutions to the transient heat conduction equation are derived by the Laplace transform technique for the cases of two and three layer samples with interfacial thermal resistance between the layers and thermal losses at the external boundaries. The use of the analytical solutions in least squares fitting programs is then discussed, with emphasis on the two layer problem. A description of FORTRAN computer programs which implement the calculations is given, with emphasis on the non-linear least squares fitting routine LSTSQRSL3. This program can determine the external boundary thermal loss factor and either the thermal diffusivity of one of the layers or the interfacial resistance between the layers. Two examples of the use of this program are given. In the first, the thermal diffusivity of an alumina layer in a graphite-alumina sample is determined, and in the second, the diffusivity of an enamel paint on a stainless steel substrate is determined. 34 refs., 12 figs., 2 tabs.},

  doi          = {10.2172/6312039},

  url          = {https://www.osti.gov/biblio/6312039},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {Wed Feb 01 00:00:00 EST 1989},

  month        = {Wed Feb 01 00:00:00 EST 1989}

}

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