Three Dimensional Simulation Analysis Of Electromagnetic Shielding Effectiveness Of Fabrics

With the development of the Internet,the number and types of electromagnetic waves in the surrounding environment are more and more.Infants and pregnant women are sensitive to electromagnetic waves,so their protection is increasingly important.Different fabrics with different structures and materials have different electromagnetic shielding effectiveness.In order to study the influencing factors of electromagnetic shielding effectiveness of fabrics,and to better design and manufacture electromagnetic shielding fabrics,this study uses rectangular waveguide method to simulate and analyze the influencing factors of electromagnetic shielding effectiveness of fabrics in ANSYS electronics software,It provides a theoretical reference for the design optimization of electromagnetic shielding fabric.Firstly,four kinds of 10%-30% stainless steel fiber blended fabrics,four kinds of 10%-30% silver plated fiber fabrics and ferrite fabrics were selected to test the shielding effectiveness of single-layer and double-layer fabrics by electromagnetic radiation tester;When the percentage of conductive material in the fabric is the same,the electromagnetic shielding effectiveness of silver plated fabric is higher than that of stainless steel fabric;The shielding effectiveness of the combination of stainless steel fiber blended fabric and silver plated fiber fabric is better than that of single fabric,and the shielding effectiveness of the first layer of silver plated fiber fabric is higher.The shielding effectiveness of ferrite coated fabric is higher than that of 30% stainless steel fiber blended fabric and 30% silver plated fiber fabric.The shielding effectiveness of ferrite coated fabric increases gradually from 0.3ghz to 0.835 ghz,and decreases gradually after0.835 ghz.Secondly,the thickness,area density,warp and weft yarn density,yarn diameter,fabric resistance,resistivity,conductivity and relative permeability of stainless steel fiber blended fabric are obtained through experiments,which can provide reference for fabric model construction and Simulation of electromagnetic parameters setting.Then,the combination model of wave source,fabric and human tissue is further established.Considering the electromagnetic characteristics of human tissue,the electric field strength of human tissue before and after shielding with different structures,materials and layers of fabric is simulated by using rectangular waveguide method in ANSYS electronics software.Then the electromagnetic shielding effectiveness of fabric is solved,and the material,thickness and thickness of fabric yarn are explored The influence of relative permeability,arrangement of conductive yarn and compatibility of double-layer fabric on electromagnetic shielding effectiveness is studied.The results show that: with the increase of the fabric thickness,the shielding effectiveness of the fabric is gradually enhanced,and the change of the electromagnetic shielding effectiveness of the fabric is gradually slowed down with the increase of the electromagnetic wave frequency,and the influence of the fabric thickness on the electromagnetic shielding effectiveness is smaller;The electromagnetic shielding effectiveness increases with the increase of relative permeability,and the change of electromagnetic shielding effectiveness slows down with the increase of relative permeability;The electromagnetic leakage mainly occurs in the fibers with low conductivity and relative permeability.The electromagnetic shielding effectiveness of the fabric woven into the conductive yarn parallel to the electric field direction is better than that of the fabric woven into the conductive yarn perpendicular to the electric field direction;The electromagnetic shielding effectiveness of ferrite yarn fabric is higher than that of stainless steel yarn fabric,the frequency is 0.3ghz-0.835 ghz,the shielding effectiveness of ferrite coated fabric increases gradually,and decreases after 0.835ghz;The electromagnetic shielding effectiveness of the first layer of ferrite yarn fabric is better than that of the second layer of ferrite yarn fabric.