A three-dimensional approach to the porous surface of screens

Improvements in the Characterisation of Permeability and Inertial Factor of Insect-Proof Screens through Pressure Drop Coefficients

“…As outlined before, the main purpose of the present investigation is to improve the classical modelling based on two-dimensional data only by adding a three-dimensional estimation of porosity. In Figure 3, the 2D and 3D characteristics of the 31 IPSs are explored by the projected pore area vs exact 3D area of screens according to [33] (Figure 3a) and the 2D vs. 3D porosities (Figure 3b). In these Figures, it can be seen that the variation of two-dimensional parameters is different from the variation of three-dimensional parameters amongst the same screens.…”

On the estimation of three-dimensional porosity of insect-proof screens

“…Thus, a superficial estimation of porosity is an useful but inaccurate approach to insect-proof screens. The importance of the 3D shape in insect-proof screens has been first considered only in the calculation of the size of the pore in [43]. However, this work only considered the size of the pore as a 2D surface corresponding to the 3D deformation in space of a rectangular pore.…”

“…This approximation yielded high errors due to the non-linearity of the hyperbolic paraboloid real area. An improvement of this calculation was carried out in [26] for insect-proof screens. In this work, it was proposed an alternative method for estimating the area of a three-dimensional porous.…”

“…Also, in other works such as [32], Computational Fluid Dynamics (CFD) are used to study the pressure drop in textile fabrics using 3D models with circular and elliptic cross-sections, which evidence the importance of the availability of 3D shapes of insect-proof screens for further computational investigation. None of the aforementioned 3D studies (except [26]) were oriented to application in insect-proof screens, and there are no works in the literature on the estimation of porosity from a 3D view. The 2D porosity modelling of screens is the standard approach even in recent applications in the literature such as e.g.…”

Estimation of the aerodynamic tortuosity of woven/wire screens

“…First, from a two-dimensional point of view [14], where it was developed a methodology to calculate (from digital microscope image processing for the identification of the vertices of pores) the separation of the threads in the x (weft) and y (warp) direction, L px and L py , the diameter of the threads in the x and y directions, D hx and D hy , and the two-dimensional porosity ϕ. Second, in [15] Alvarez and coworkers made an approximation to the three-dimensional area of the pore, being the first attempt in the literature. However, despite this method was suggested for improving the estimation of threedimensional porosity, in reality this approach was based on planar properties.…”