Thermal Modeling of a Multilayer Insulation System

An analytical investigation of a novel multilayer insulation concept was conducted using an extended analytical model. This model was developed to accommodate a multilayer screen wire insulation system with interstitial shim layers. The goal of this study was to provide a simplified model for evaluating this insulation system, which included either a single or multilayer composite structure in order to predict optimal performance. With the present model, the feasibility and performance characteristics of the insulation concept were predicted. The thermal predictions have demonstrated a very good comparison with previously published experimental data. By adding a radiative resistance to the model, improved performance predictions of overall thermal resistance/conductance were possible, leading to the extension of single layer analytical model to multiple-layered cases. From the parametric study, the key thermophysical property of the screen wire was found to be the wire’s thermal conductivity. The present model provided excellent performance prediction capability for other screen wire materials, and these results were also validated with a comparison to previously published experimental results.