Optimization Simulation on Blade Number of Grit Chambers with Rotational Flow

Abstract:

The grit chambers with rotational flow find wide range of application for the treatment of sandstone wastewater in hydropower stations. Aiming at the high-turbidity solid-liquid two-phase problem of a complex flow pattern, an Eulerian-Eulerian two-phase model was built, which can describe the collision term between particles in sandstone wastewater. By using CFD technology, the velocity distribution of flow at the blade position was analyzed and the different effects caused by blade numbers to the particle removal efficiency were discussed. The results show that the removal efficiency of grit chamber with rotational flow increased gradually at first and then decreased slightly. Then the number of blade is four, the optimum removal efficiency can be reached, which provided theoretical and referential basis for engineering design and operation.

• Periodical: Applied Mechanics and Materials (Volumes 368-370)
• Pages: 1894-1897
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.368-370.1894
• Online since: August 2013
• Authors: Rui Rui Sun, Xiao Ling Wang, Jia Min Tu, Xue Fei Ao
• Keywords: Blade Numbers, Eulerian-Eulerian Two-Phase Model, Grit Chamber with Rotational Flow, Removal Efficiency

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