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%≤β≤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

Feasibility study on the use of carbonized cassava cortex as reinforcement in polymer-matrix composites

The feasibility of using carbonized cassava cortex (CCCtx) as reinforcement in polymer-matrix composites was studied by experimental investigation of the composites’ mechanical properties. The cortex was raised to a temperature of 550°C to get it carbonized and was subsequently milled to powder form. The powder was sieved into particle sizes of 150, 300, and 600 μm. Polymer-matrix composite materials were produced from them using thermosetting resin. Analyses of the energy dispersive spectroscope spectrum and X-ray diffraction of the CCCtx were carried out. The carbonized particles’ surface morphology was revealed by electron microscopy. The thermogravimetric analysis was also carried out. The component samples produced were tested for tensile strength, flexural strength, compressive strength, impact strength, elastic modulus, and hardness. For the evaluation of the composites, the particle sizes effect and wt% composition on the properties were studied and used as the criteria. The results showed that CCCtx can be used in reinforcing polyester resin