Two-phase (water and air) flow in the forced-air mechanically-stirred Dorr-Oliver machine has been investigated using computational fluid dynamics (CFD). A 6 m 3 model is considered. The flow is modeled by the Euler-Euler approach, and transport equations are solved using software ANSYS-CFX5. Unsteady simulations are conducted in a 180-degree sector with periodic boundary conditions. Air is injected into the rotor at the rate of 2.63 m 3 /min, and a uniform bubble diameter is specified. The effects of bubble diameter on velocity field and air volume fraction are determined by conducting simulations for three diameters of 0.5, 1.0, and 2.0 mm. Air volume fraction contours, velocity profiles, and turbulent kinetic energy profiles in different parts of the machine are presented and discussed. Results have been compared to experimental data, and good agreement is obtained for the mean velocity and turbulent kinetic energy profiles in the rotor-stator gap and in the jet region outside stator blades.Keywords: minerals flotation machines; void fraction; two phase flows; numerical simulation Abbreviations: Air/water dynamic viscosity, Pa s, (water, i = 1 and air i = 2) ρ i Air/water density, kg/m 3 , (water, i = 1 and air i = 2)
The primary purpose of this thesis is to quantify the effects of RANS turbulence modeling on the resolution of free shear vortical flows. The simulation of aerodynamic wing-tip vortices is used as a test bed. The primary configuration is flow over an isolated finite wing with aspect ratio, iii ACKNOWLEDGEMENTS
My thanks are due to Mr. Mohammad Elyyan and my daughter Noura for their help in the presentation and Tecplot. I would like to thank the Department of Engineering Science and Mechanics for supporting me financially through GTAs. My gratitude is due to the Egyptian embassy for supporting me financially throughout my stay in the USA. v xiv List of Tables 3.1 The a m coefficients of fourth-order Runge-Kutta scheme [54]. .. .. .. . 3.2 The b m coefficients of fourth-order Runge-Kutta scheme [54]. .. .. .. .
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.