LABORATORY SIMULATION OF LIGHTNING DIRECT EFFECT USING GRIFON TEST BENCH AT ONERA

摘要

The interaction between a lightning arc and composite materials is studied at ONERA using a new test bench called GRIFON. This test bench delivers DBC~* current waveform according to SAE standard ARP5412. It is composed of three branches: a high voltage one to deliver the D component and two low voltage branches to deliver the B and C~* component. A typical test involved a 40×40 cm panel as the sample and several diagnostics are used simultaneously: current measurement, fast imaging and correlation-based stereo. The aim of this study is to analyse the interaction between the arc and different panels. To achieve this goal, multiple parameters have been tested: type of material (e.g. aluminium or composite), paint thickness, sample thickness, protected to lightning or not. For each case, dynamic of the arc root is observed using fast imaging cameras at 500 kfps. Additionally, the mechanical strain of non punctured panel is obtained using correlation-based stereo vision at 16 kfps. Strain in the order of several mm with a precision of 100 μm and punctured delay are measured. Moreover, profile of mechanical strain is obtained and depending on the material, different propagation mode inside the material are observed and discussed.