Experimental and numerical study of gas hold-up in surface aerated stirred tanks

摘要: Although the distribution of gas hold-up in stirred tanks is a key factor to their design and operation, systematic experimental data on local surface-aerated are not available open literature. In this work, turbulent two-phase flow surface aeration tank with diameter 0.380m was investigated experimentally numerically. The measured conductance probe at various operating conditions. A baffle improve efficiency Rushton disk turbine designed tested. suggest that very non-uniform, improves rate particularly high agitation speed. three-dimensional in-house computational fluid dynamic (CFD) two-fluid model standard k-epsilon-A(P) turbulence used predict gas-liquid flow, impeller region handled using improved inner-outer iterative procedure. Based Kolmogoroff's theory isotropic turbulence, constitutive equation for strength proposed. numerical prediction, combination measurements, gives insight performance tanks. it found simulation reasonably predicted upper tank, but underestimated below stirrer. (c) 2006 Elsevier Ltd. All rights reserved.