Study on fire precursor of wire insulation in low-pressure environments

The damage and overheating of wire insulation are main ignition source in the fire incidents of the manned spacecraft in microgravity. It is of great important significance to study on fire initiation of the wire insulation in microgravity for fire safety in the manned spacecraft. In this paper, the effects of ambient pressure, wire diameter, wire bundle number and overloaded currents were examined with emphasis on the steady equilibrium temperature and temperature increasing rates of the wire insulation by the use of the functional simulation method. The results are of significance for the study of the fire precursor at microgravity and were used to determine the experimental parameters on board the SJ-8 China recoverable satellite.