Dielectric Constant And Anisotropy Study The Interaction Mechanism Between Fabric And Electromagnetic Waves

Due to its excellent electromagnetic properties,the advantages of soft and light textile materials,electromagnetic textile has become an important part of high-performance electromagnetic functional materials.Therefore,the study of electromagnetic wave propagation in fabrics based on electromagnetic field theory becomes very important research topic.The purpose of this research is to realize the electromagnetic simulation of the fabric three-dimensional structure,and to calculate the fabric structure,electromagnetic parameters and fabric anisotropy and other factors on the electromagnetic properties of fabric,laying a foundation for the realization of electromagnetic textile digital design.In this paper,we first use TexGen software to build the three-dimensional structure model of plain weave,twill and 5/3 weft satin weave,and get the laminated fabric model and single-sided,double-sided symmetrical and double-sided asymmetric finishing fabric model,in order to achieve fabric electromagnetic simulation in preparation.The CST simulation environment used in this experiment is theoretically verified,which provides a guarantee for the follow-up research.According to building the model of electromagnetic fabric and electromagnetically simulating it by CST software,the physical process of the interaction between fabric and the electromagnetic wave is researched,and the influence of the dielectric constant of the fabric on the reflectivity and the transmittance is calculated in the range of 1-18GHz frequency.Experimental results indicate that when the dielectric constant changes of fabrics,the dielectric constant increased reflectivity decreases and the transmittance increases,the results with the medium plate instead.Through microscopic analysis,this mainly due to the impact of the complex structure of fabric.Based on the microstructure analysis and modeling of the anisotropic electromagnetic shielding fabric,the electromagnetic simulation is carried out by CST software.The influence of the incidence angle and azimuth of electromagnetic wave on the anisotropic fabric in the 1-18GHz frequency range is studied,and the influence of the different structure and spacing of the anisotropic fabric on the shielding effectiveness is simulated and analyzed.Experimental results indicate that when the dielectric constant is small and the angle of the incident electromagnetic wave increases,the shielding effectiveness increases first and then decreases gradually.The dielectric constant of X axis and Y axis has a significant influence on the shielding effectiveness of the fabric,and the change of dielectric constant in the direction of Z axis has little effect on the shielding effectiveness of the fabric.When the azimuth of the electromagnetic wave is changed,the changing trend is different with the dielectric constant of the anisotropic fabric.But when the azimuth angle is 45 degrees,the changing trend of shielding effectiveness is the same in the low frequency section with the change of incidence angle,which is not affected by the change of dielectric constant.The anisotropy of the fabric shielding effectiveness is better than isotropic fabric,while for the twill and satin,influence of anisotropic properties on the shielding effectiveness is very small.The larger the porosity of the anisotropic fabric,the worse the shielding effectiveness.It is very important to design the new electromagnetic shielding fabric by selecting the best electromagnetic parameters and the fabric structure.