Analysis of Lightning Current in Composite Materials for Civil Aircraft Based on EMA3D

Composite materials have the characteristic of anisotropic low conductivity. Currently， most aircraft lightning current simulations focus on the study of metal materials， which makes it difficult to effectively characterize the surface current density distribution and transient current conduction of composite materials aircraft after lightning strikes. To ensure the effectiveness of lightning protection design and analysis of composite materials for civil aircraft， the anisotropic conductivity matrix under the influence of layer and fiber content is introduced into the three-dimensional time-domain finite difference method to analyze the principle of lightning current conduction in composite materials. Based on EMA3D simulation software， lightning current analysis is carried out， and simulation verification is carried out under multiple injection paths on a civil aircraft with equivalent composite materials skin. The results without protective measures indicate that the current density is high in the local area of the impact point and sharp parts such as the front and rear edges of the wing， and there is a phenomenon of current concentration； the current preferentially conducts along the axis of the fuselage when subjected to lightning at the nose of the aircraft， and it preferentially conducts along the spanwise direction of the front and rear edges of the wing when struck from the wing； Transient current has conduction hysteresis compared to metal materials in civil aircraft.