Model of the hydrodynamic loads applied on a rotating halfbridge belonging to a circular settling tank

• Published in: IOP conference series. Materials Science and Engineering 2016-08, Vol.145 (4), p.42008-42014
• Main Authors: Dascalescu, A E, Lazaroiu, G, Scupi, A A, Oanta, E
• Format: Article
• Language: English
• Subjects: Access bridges; Computational fluid dynamics; Energy dissipation; Finite element method; Finite volume method; Fluid flow; Hydrodynamics; Kinetic energy; Loads (forces); Mathematical models; Multiphase flow; Navier-Stokes equations; Numerical models; Pipes; Reynolds averaged Navier-Stokes method; Rotation; Sedimentation tanks; Sludge; Stress concentration; Suction; Turbulence; Turbulent flow; Wastewater; Weight
• ISSN: 1757-8981; 1757-899X
• DOI: 10.1088/1757-899X/145/4/042008

The rotating half-bridge of a settling tank is employed to sweep the sludge from the wastewater and to vacuum and sent it to the central collector. It has a complex geometry but the main beam may be considered a slender bar loaded by the following category of forces: concentrated forces produced by the weight of the scrapping system of blades, suction pipes, local sludge collecting chamber, plus the sludge in the horizontal sludge transporting pipes; forces produced by the access bridge; buoyant forces produced by the floating barrels according to Archimedes' principle; distributed forces produced by the weight of the main bridge; hydrodynamic forces. In order to evaluate the hydrodynamic loads we have conceived a numerical model based on the finite volume method, using the ANSYS-Fluent software. To model the flow we used the equations of Reynolds Averaged Navier-Stokes (RANS) for liquids together with Volume of Fluid model (VOF) for multiphase flows. For turbulent model k-epsilon we used the equation for turbulent kinetic energy k and dissipation epsilon. These results will be used to increase the accuracy of the loads' sub-model in the theoretical models, e. the finite element model and the analytical model.