New method for evaluating the kinetic constant of thermal protection materials

Abstract

Thermal protection material (TPM) is used to protect rocket structures from extreme conditions created by the hot exhaust of the rocket. Designing TPM is an important step in the rocket design process. Considering that an increase in the system weight decreases the overall performance of a rocket, the amount of TPM is carefully determined during the design process. Therefore, the precise properties of TPM guarantee an accurate thermal analysis and the successful design of the rocket. Among the many properties of TPM, the kinetic constant and activation energy, which govern the thermochemical reaction of the TPM, are the most important. Thus, an experiment to measure the kinetic constant and activation energy is conducted as part of this research. A theoretical approach to deduce the properties from measured data is discussed, and a method to apply the theory to experimental data, termed the R2 method, is developed. Compared to a previous method which was difficult to apply, the R2 method reduces unclear selections of the reaction time and does not require intervention by an interpreter. The properties deduced by the R2 method show good agreement with the other method despite the limited number of experimental results.