Simultaneous measurement of six thermal properties of a charring plastic

Abstract

Six thermal properties of a charring carbon-phenolic material are measured in a single experiment. The experiment, performed in two hyperthermal plasma-arc facilities, is described and a heat-transfer model is presented, an extension of the classical fusion model of Stefan. The model is solved using a method of finite differences which has several unique features. The properties are calculated from the experimental measurements using the model and nonlinear regression analysis. The calculated property values are shown to be in good agreement with values from conventional tests. It is demonstrated by comparative calculations that the modified Stefan model with nonlinear-regression properties predicts the transient thermal behavior equally as well as a more sophisticated ablation model with conventionally measured properties.