積層型複合断熱材の断熱性能と熱変形挙動の有限要素法解析

抄録

This research aims to simulate thermal distribution and deformation of composite heat insulation, which is usable as thermal expansion mats in catalytic converters for vehicles. Experiments are also carried out to determine material constants such as thermal conductivity and coefficient of thermal expansion (CTE) for each constituent material. The FEM simulations include a 2D plane-strain model representing a stacking structure with silica-fiber mats (SFM) and nano-porous heat insulation (NPI). NPI is inserted as a core-layer between two SFMs, and silicon carbide (SiC) is also added in NPI to prevent heat radiation. The analytical results indicate that the NPI core-layer has a significant thermal insulation effect on the whole model. The analytical and experimental results show a good agreement when the composite heat insulation is heated up to 500°C; however, the difference becomes evident above that temperature due to the influence of heat radiation from the heat source. Thermal shrinkage of the composite heat insulation can be predicted by the FEM simulations and compared with the experimental results. They suggest that the thickness of the composite heat insulation must be adjusted to be used in catalytic converters for vehicles.