Результаты расчетно-экспериментальных исследований электротермической стойкости опытных образцов из листовой стали к воздействию нормированных компонент импульсного тока искусственной молнии

Abstract

Purpose. Calculation and experimental researches of the electro- thermal resistibility of the steel sheet samples to action standard pulse current components of the artificial lightning with amplitude-time parameters (ATP), corresponded the requirements of normative documents of USA for SAE ARP 5412 & SAE ARP 5416. Methodology. Electrophysics bases of technique of high tensions and large impulsive currents (LIC), and also scientific and technical bases of planning of devices of highvoltage impulsive technique and measuring in them LIC. Сurrent amplitude ImA=±200 kA (with a tolerance of ±10 %); current action integral JA=2·106 A2·s (with a tolerance of ±20 %); time, corresponding to the amplitude of the current ImA, tmA≤50 microseconds; the duration of the current flow τpA≤500 microseconds. Results. The results of the evaluation of the calculated and experimental studies of electro-thermal resistance of the samples of plates measuring 0,5 m  0,5 m stainless steel 1 mm thickness to the action on them artificial lightning impulse currents with rationed ATP on the requirements of normative documents of USA for SAE ARP 5412 & SAE ARP 5416. A pulse A- component have a first amplitude 192 kA, the corresponding time of 34 μs, and the duration aperiodic component amplitude 804 A, corresponding to the time 9 ms. It has been shown that the long C- component current of artificial lightning can lead to keyhole these samples. The diameter of the holes in this thin steel sheet, which is formed during the flow of current C- components can reach 15 mm. The results of calculation and experiment agree within 28 %. Originality. For the first time in world practice on the generator large pulsed currents experimental studies of resistibility of sheet steel samples to the action of artificial lightning currents with critical parameters. Practical value. Using the results obtained in the practice of lightning protection will significantly improve the functionality and fire safety of different objects in conditions of exposure to linear lightning