Integral Fuel Tank Skin Material Heating from Swept Simulated Lightning Discharges.

摘要

Studies have been carried out to determine the hot spot temperatures of swept laboratory lightning discharges using an infra red scanning camera, modified to provide higher time resolution with the LTRI St. Paul wind tunnel used to sweep the stroke. The data was compared with non swept (stationary arc) data. Somewhat higher energies were used in the test discharges corresponding to the new waveforms (SAE-Task F) including a 100,000 restrike and a 15 coulomb intermediate component superimposed on two hundred amperes of continuing current typical of natural lightning. The results indicate that with the thinner new materials, a hot spot ignition hazard definitely exists for the lower conductivity materials, titanium and stainless steel but less than had been previously estimated. Yet to be determined is the complete envelope of hot spot time duration versus temperature required for ignition. (Author)