Table 5. Woven fabric sample parameters. Max. Aperture width L 50 mm 5 mm aperture spacing a 1 mm Sample 1 Sample 2 Sample 3 1 mm 2 mm 2 mm weight) and SE is made. Sample 1 is selected as the basis for weaving properties of woven fabric. EXPERIMENTATION Sample 1 is chosen as a reference the analytical and numerical simulation. The aperture parameters mainly aperture size and spacing is translated to the appropriate weft and warp yarn densities. The properties of the woven fabric are listed in the Table 6. Woven fabric is shown in Figure 8. Shielding Effectiveness Measurement (ASTM D4935) ASTM D4935 is the standard used for measurement method used to test the shielding effectiveness of the Aluminum woven fabric. This technique is convenient for the SE measurements of flat and thin materials, especially for composite materials as shown in Figure 9. This set up is used for the plane wave SE measurements for high frequencies (100 MHz - 10 GHZ)5 . The difference of signal power between the signal generator and spectrum analyzer gives the shielding capacity of the sample material. The first step is to place the reference sample between the flanges in the middle of the cell, concealing only the flanges and the inner conductors. Then a load measurement is achieved on a solid disk shape that has a diameter the same as that of the flange. The reference and load measurement are executed on the same material having the same thickness. The SE is defined as the logarithm of the ratio of power received with the load specimen Pload reference specimen in place PReference equation5 to the as given by the . Figure 7. Shielding effectiveness vs aperture parameters. Reference Sample 1 Maximum aperture size 50 mm Aperture spacing Warp yarn density Weft yarn density Yarn linear density Fabric weight 1 mm 15 yarns/cm 10 yarns/cm 30 tex 72 g/m2 Table 6. Weaving parameters. Figure 6. Shielding effectiveness. RESULTS Numerical Simulation Sample 1 is used as the basis for the investigations. The simplified 2D model of the woven fabric with aperture size corresponding to sample 1 is shown in Table 5. The model is imported and simulated in Ansys Electromagnetics software, USA. Ansys solver uses maxwell equations as the governing equations for electromagnetic shielding. The electrical parameters of aluminum given in Table 7 is used here. Table 7 shows the simulation parameters. www. sampe.org JANUARY/FEBRUARY 2022 | SAMPE JOURNAL | 21https://www.pccomposites.com/ http://www.sampe.org