Fine Mesh Dutch Twill meshes

Table B.1 Fine Mesh Dutch Twill Meshes...

Figure 4.17 shows a sample of the wicking distance as a function of time for the three fine mesh Dutch Twill samples. As shown, the wicking distance is proportional to the square root of time, as predicted by Equation (3.65). The fastest wicking distance occurs with the coarsest screen, consistent with historical trends. 

As speculated in Chapters 4 and 5 it is believed that the shape of the actual pore structure is a secondary influence (the primary influence being the fineness of the screen) on the effective pore diameter. For example, for Dutch Twill meshes, these openings are complex 3D structures. The equilibrium L/V interface shape is complex and it depends on the size and packing of the wires. If it were possible to observe microscopically a L/V interface within a Dutch Twill weave, it might be possible to imderstand why the 450 X 2750 outperforms the 510 x 3600. Meanwhile, it is much more efficacious to look at deeper correlations between the pore diameter and geometrical properties of the mesh like the warp and shute wire diameters. Since the warp and shute diameters are a maj or factor in determining the pore shape it is likely that they have a relationship with the pore diameter. 

X 2300 SS, 200 x 1400 SS, and 200 x 1400 A1 from Paynter (1973a). The Ka values are listed in Table 3.6. For a given APd the maximum deflection occurred for the 200 X 1400 A1 screen, as expected, since it is made of a more elastic material than the other two screens. When comparing meshes of the same metal, the 200 x 1400 SS had a smaller. Kd value than the 325 x 2300 SS mesh. This supports the trend that finer meshes experience more deflection, or compliance, than coarser meshes for the same pressure difference and same metal. Since fine mesh screens are generally desirable for LH2 systems, additional screen compliance tests with these fine mesh Dutch Twill screens would help to verify this trend. 

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