Executive Summary : | since the advent of polymers, they are replacing in increasing proportion the conventional materials such as wood, metals, earth and concrete. However, these changes have resulted in much higher risk of fire to human life and property. The fire safety requirements become more stringent in micro-gravity space environments, especially for in human space missions. Human endeavors in space are on increase and India has also set out plans for human mission in space in near future. It has been reported that the physical phenomena in space are quite different from those on earth and often counter intuitive. since these effects cannot be reproduced in earth's gravity, there is need to access space environment. However, accessing space environment poses a big challenge in terms of accessibility, time and cost. The proposed work focuses on assessing fire behavior of polymer-composite-polymer layered composite materials commonly found in the form of wire with insulations, tera pack, retort pouches etc. in both earth and space environments. The approach comprises of experiments, complemented with numerical modelling to assess the fire safety of such materials when used on earth and in space. Towards this it is proposed here to develop an experimental setup to study flame spread and extinction over solid materials in normal gravity and micro-gravity environments. The 2.5 s micro-gravity Drop Tower of NCCRD at IIT Madras, which is the only micro-gravity facility available in the country will be used for the micro-gravity experiments. Numerical model of flame spread over thin polymer-metal-polymer will be developed from and existing code on flame spread. Both cylindrical geometry of wire with polymer coat and planar geometry metal sandwiched between polymer will be modeled and validated with experimental data. Finally controlling mechanisms of flame spread rate and extinction in polymer-metal-polymer materials will be elucidated. |