碳纤维增强复合材料薄层高效建模方法研究

High efficient modeling techniques of carbon fiber reinforced composite thin layer

作为金属的替代品,碳纤维增强复合材料已被越来越广泛地用于飞行器、舰船和导弹等目标的壳体制造,而碳纤维增强复合材料的屏蔽效能对目标体的电磁安全起着重要作用.采用常规的全波分析方法计算碳纤维增强复合材料的屏蔽效能存在两大难题:复杂的材料属性和薄层带来的电大多尺度问题.为实现对碳纤维增强复合材料薄层的高效建模,通常采用均匀化的方法来等效具有复杂材料属性的复合材料,采用嵌入式薄层模型技术解决电大多尺度问题.本文将从均匀化方法和嵌入式薄层模型技术两个方面来探讨碳纤维增强复合材料薄层高效建模方法,并概述自主研发的大规模并行全波分析软件JEMS-FDTD及其集成的嵌入式薄层模型技术.最后,通过计算实例说明集成了嵌入式薄层模型的JEMS-FDTD软件在对碳纤维增强复合材料进行建模的正确性和高效性,并通过模拟仿真壳体为碳纤维增强复合材料飞机的屏蔽效能,说明集成了嵌入式薄层模型的JEMS-FDTD软件的实际应用价值.

Carbon fibre reinforced composite (CFRC) materials have been widely adopted as replacement of metals for the construction of enclosures of platform targets, such as aircraft, ships, missiles, and so on. The shielding properties of CFRC materials play an important role in the electromagnetic safety of platform targets. There have been two difficulties in the calculation of shielding effectiveness of CFRC thin layer using the conventional full wave numerical methods: the complicated material properties of CFRC materials and the electrically large multi-scale problem due to the small thickness of CFRC thin layer. To overcome these two difficulties, homogeneous methods have been developed to obtain the equivalent homogeneous materials to the composite materials with complicated material properties and the embedded thin layer model techniques have been proposed to solve the electrically large multi-scale problems. In this paper, the high efficiently modelling techniques of CFRC thin layers will be discussed, from the perspective of homogenous method and embedded thin layer modelling techniques. Furthermore, the embedded thin layer technique integrated into the massively parallel full wave numerical software, JEMS-FDTD, will be briefly presented. In the end, the accuracy and high efficiency of JEMS-FDTD with the embedded thin layer modelling technique will be discussed using a numerical example. Besides, the shielding effectiveness of an aircraft with its skin made of CFRC materials will be calculated using JEMS-FDTD with the embedded thin layer technique, which indicates its applicability.