Molten thermoplastic dripping behavior induced by flame spread over wire insulation under overload currents

摘要: The dripping behavior of the molten thermoplastic insulation copper wire, induced by flame spread under overload currents, was investigated for a better understanding energized electrical wire fires. Three types sample with same polyethylene thickness and different core diameters, were used in this study. First, current effects on transient one-dimensional temperature profile predicted using simplified theoretical analysis; heating process equilibrium obtained. Second, experiments melting characteristics conducted laboratory environment, including drop formation frequency, falling speed, combustion steel base. Third, relationship between mass loss volume variation proposed to evaluate time frequency. A strong prerequisite averaged frequency found be proportional square based experimental results. Finally, influence propagation along discussed. width, bright height spreading velocity presented behaviors.