Investigation on the effective thermal conductivity of carbonized high silica/phenolic ablative material

摘要

As a phenolic resin-based ablative material, high silica/phenolic composite is widely used in aerospace field. However, the effective thermal conductivity of carbonized ablative material formed during ablation process is rarely reported. In this work, carbonized sample of the high silica/phenolic ablative material was obtained by a carbonization process, and its effective thermal conductivity was measured from 100 to 970 ℃. In addition, an analysis model of the effective thermal conductivity of the carbonized ablator consisting of fiber yarns and carbonized phenolic was established based on the result of structure analysis. The measured value of the effective thermal conductivity of the carbonized phenolic was used to inverse the transverse effective thermal conductivity of the fiber yarns. When the inversed values were adopted in different empirical models, it was found that the Clayton model is suitable for predicting the effective thermal conductivity of the carbonized high silica/phenolic.