Track: Design and Analysis

Abstract

As the South African population grows, so too is the demand for clean water. There are numerous methods that have been developed over the years for cleaning water. Water purification technologies at Veolia Water Technologies, in Johannesburg, South Africa, is focused on increasing the quality of purified water. The main focus of this study is to use literature to get a fundamental understanding of Clarification technologies. study presents the Finite Element Analysis (FEA) of an Actiflo Clarifier designed by Veolia Wastewater Technologist in Johannesburg, South Africa. Various aspects are investigated in this study. There are membrane tensile stresses on the Actiflo walls due to the hydrostatic pressure of the liquid which causes buckling. Stiffeners are inserted to counter the buckling effect and maintain structural rigidity. A model is developed to simulate the tensile stresses acting along the span of the stiffeners through its cross section. FEA is carried out and the results correlates with results from calculations based on the theory of structural buckling. The Actiflo Clarifier stiffeners are assumed to meet the Euler buckling criterion. The maximum deflection occurs at the top of the tank where the actual pressure is far less than the 40kPa at the bottom of the tank which was assumed to be the maximum pressure acting constantly along the walls of the Actiflo.

Various parameters such as fatigue failure, design variables, as well as the different stiffener positions and sections used to determine the local bucking points of the rectangular structure are tested in the Finite Element Analysis (FEA) environment using Ansys. The Finite Element Method (FEM) is used to determine the critical zones of large deformations and stresses as well as to test theoretical principles. The design process in its entirety detailed throughout this dissertation, including methodology, analyses and end results is presented herein.