Temperature Distribution in a Composite Box Structure Subject to Transient Heat Fluxes

Autor: JR Miller, Paul M. Weaver
Rok vydání: 2003
Předmět:
Zdroj: Journal of Thermophysics and Heat Transfer. 17:269-277
ISSN: 1533-6808
0887-8722
DOI: 10.2514/2.6762
Popis: Finite element and analytical approaches are used to determine the transient temperature distribution through an air-filled box structure with CFRP skins. A study of the individual and combined effects of conduction, convection, and radiation boundary conditions is performed. A novel method for the inclusion of natural convection within a cavity using ABAQUS is presented. The method uses ABAQUS' capability to model natural convection on an external surface, in combination with results obtained via conduction analysis through the cavity, in order to simulate natural convection. It is shown that although the effects of natural convection within the cavity are less significant than that of radiation, they are not negligible, and thus should not be excluded from the analysis. Analytical models, based on integral transforms, are developed to describe the temperature distribution through the skin subject to combined thermal loading conditions. Fully transient convection conditions, as well as combined semitransient convection-radiation conditions are modelled, and the limits of such analytical solutions are explored. The analytical modelling of such combined conditions using integral transforms is novel, and is found to compare well with FE results. Nomenclature q = heat flux (W/m2) k = conductivity (W/m) h = convection heat transfer coefficient (W/m2) T^ = sink or reference temperature (K) Ts = surface temperature (K) a = Stephan-Boltzmann constant (5.669x10"8 w/m2K4) e = surface emissivity t = time (s) TI = initial temperature (t=0) L = skin thickness (mm) x = position through thickness of skin (mm) pm = eigenvalues m = number of series terms a = thermal diffusivity (m2/s) H = h/k (in1)
Databáze: OpenAIRE
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