Thermal conductivity of metal coated polymer foam: Integrated experimental and modeling study

Foams offer extremely large surface area per unit mass, making them competitive material for heat exchangers and energy storage systems. Understanding the influence of foam characteristics, i.e., size, distribution and concentration of pores, ligament defects as well as foam architecture, on thermal transport is important when designing the foam-based devices. In this article, we present the effective thermal conductivity of open-cell polyurethane (PU) foam (20 PPI) with ~10 μm thick nickel coating measured by transient plane source (TPS) method. A calibration methodology for TPS method is developed to obtain accurate measurements. A finite element model and thermal resistance model are developed for the heat transfer in metal coated foams occurring near room temperature. For precisely modeling the foam architecture topology, an X-Ray tomography is employed. The developed models are used to investigate how the Ni coating thickness affects the effective thermal conductivity. Lastly, we discuss how the model assumptions are related to the discrepancy between the model predictions and measurements for the polymer-metal foams.