ScholarWorks@경상국립대학교

초록

Lightning strikes can cause catastrophic damage to composite structures, particularly carbon/epoxy laminates. This study presents a comparative analysis of structural damage induced by different physical phenomena associated with lightning strikes. Three primary factors were independently investigated through numerical simulations: (1) Joule heating, (2) shock wave overpressure (SWO), and (3) heat flux. An electric current waveform A, with a peak amplitude of 40 kA, was used to represent artificial lightning and to derive both the SWO and heat flux parameters. A carbon/epoxy composite panel with dimensions 150 x 150 x 1.0 mm (length x width x thickness) was modeled using the Abaqus6.14 simulation package. A degradation temperature of approximately 300 degrees C was defined for thermal failure onset under both Joule heating and heat flux conditions. For mechanical damage analysis, the Hashin's failure criteria were employed to predict fiber and matrix damage resulting from shock wave loading. Simulation results revealed that Joule heating was the most destructive factor, causing a volume damage ratio of 4.14 %. In contrast, no mechanical damage was observed under SWO, while heat flux resulted in only a minor damage ratio of 0.03 %. Additional findings on the thermal and mechanical responses in both in-plane and through-thickness directions are discussed in detail.

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