Study on Fire Initiation of Wire Insulation by a Narrow Channel at low Pressure

A low-pressure narrow channel method (LPNCM) was proposed in this paper to study the fire initiation of wire insulation in microgravity. The detailed principles for parameter choices of LPNCM were discussed. Based on this method, a weakly buoyant environmental setup was established and the effects of overloaded current on the fire initiation of wire insulation were investigated systematically. Results show that if the ambient pressure was reduced to a proper range, the method could effectively investigate the flammability of wire insulation in the weakly buoyancy environment by increasing the narrow channel height. It can overcome the shortages in the conventional narrow channel method by decreasing the pressure to a proper extent. The observed fire initiation characteristics of wire insulation using LPNCM are similar with those conducted in microgravity. Thus, the presented method provides a new tool to conduct experiments of thermally thick fuels at normal gravity to simulate the fire initiation in microgravity.