In the Thermo-Physical Characterization Facility at Sandia National Laboratories, we study the thermal properties of a wide range of materials for different applications. In this presentation, we are going to talk about our current studies with thermal barrier materials, in particular for engines and advanced thermal insulation.
Thermal barrier coatings (TBCs) are intended for application to combustion chamber surfaces to improve efficiency, but TBCs’ actual impact on engine efficiency is highly variable. We believe that TBCs can improve engine efficiency, but only if their development is driven by material property requirements. Rarely are the thermophysical properties of TBC coating well characterized beyond the manufacturing specifications. Currently, we collaborate with combustion research facility (CFR) scientists to develop requirements-driven materials informed by in-situ, in-use characterization of interaction mechanisms between TBCs and diesel combustion processes. Because the microstructure of the coating varies from the bulk coating material, the measurement capabilities of the thermophysical properties lab will be utilized to accurately quantify aggregate coating properties, while Sandia’s medium-duty diesel engine research laboratory will be augmented to quantify heat losses by measuring exhaust and oil/coolant enthalpy flows.
We are also actively working in the development of advanced thermal materials to meet complex thermal insulation needs that traditional foams cannot completely fulfill. One of the big issues of thermal insulation is the overheating of internal electronics. We developed techniques to accurately measure the thermal properties of anisotropic insulation materials that can control the directionality of the heat flow. At the Thermo-Physical Characterization Facility, we believe that custom designs and innovative techniques are needed to accurately measure and develop thermal barrier materials for real applications.