Role of Thermal Contact Conductance on Sandwich-Type Metallic Thermal Protection System Profile.

In a sandwich-type metallic thermal protection system (MTPS), the contact between the skin and the corrugated core is an important parameter that determines the heat transfer across it. Thermal contact conductance (TCC) between the skin and core is considered in the present transient heat transfer analysis following three-dimensional heat transfer equations for a simplified MTPS filled with insulation for a period of 1000 s. Experimental results on a thermal profile across the MTPS are obtained for two time-varying heat flux histories; for a selected heat flux history, the value of TCC is varied in the analysis. The value that shows close agreement with the test data is then taken for further analysis for the second heat-flux history. A comparison of the surface temperatures and associated duration on the top skin, below the skin, below the horizontal flange connecting the two adjacent webs of the corrugated core, and at the back wall obtained by analysis and testing shows good agreement for the top skin, whereas a qualitative agreement is seen for the back wall with the temperature-dependent properties considered. The study indicates that a higher value of TCC leads to a conservative estimation of the back-wall temperature. [ABSTRACT FROM AUTHOR]