Two-Dimensional Simplification of Complex Three-Dimensional Wire Mesh Screens

This paper presents an approach to accurately characterize three-dimensional (3D) wire screen geometries as simplified two-dimensional (2D) screens for low Reynolds numbers. This is achieved by identifying 2D screen geometric features that provide appropriate approximations to a 3D realistic wire screen geometry. The simplified 2D screen geometries are obtained by varying geometric characteristics such as the streamwise pitch to diameter ratio within the range of 0 <= C/D <= 1 for side-by-side cylinders. Both in-line and staggered cylinders with spanwise pitch to diameter ratios ranging from 2.94 <= P/D <= 5.56 are examined here. A parametric study is performed for equivalent wire screen open area ratios varying within the range of 43.56% <= beta <= 67.26%. Numerical flow field comparisons between a 3D wire screen and its approximate 2D simplification are performed, with results further validated against documented experiments. The equivalent 2D flow loss coefficients agree very closely with the full 3D results, where for some Reynolds numbers, they are found to be within 6% of the experimental results. Both 2D and 3D results are found to underpredict the experimental values. The 2D results are also found to be much more accurate than the well-known flow correlations that are commonly used. 2D turbulence intensities measured at 570 diameters downstream of the screen were found to have the same values as the experimental results for some Reynolds numbers and were within 10% at worst. This demonstrates a real advantage over a 3D model, where such a long numerical domain would be very computationally expensive. Out-of-phase vortex shedding patterns exist for both in-line and staggered screen configurations in the range of 0 <= C/D <= 1. The contribution of this work will enable design studies to perform preliminary fast analysis of the effect of wire screens when applied as flow or noise control technologies. (C) 2021 American Society of Civil Engineers.

Automated summary

This study presents a method to accurately characterize the geometries of 3D wire screens as simplified 2D screens for low Reynolds numbers. By comparing numerical flow fields and validating with experimental results, it is found that the simplified 2D models closely match the full 3D results and are more accurate than commonly used flow correlations. The research contributes to design studies by enabling fast analysis of the impact of wire screens in flow or noise control applications.