Large eddy simulation of the gasliquid flow in a stirred tank

Both the large eddy simulation (LES) technique and the k-epsilon turbulent model were used to simulate the gas-liquid turbulent flow in a stirred tank driven by a Rushton impeller. A Eulerian-Eulerian two-fluid model for gas-liquid two-phase flow, was developed using the large eddy,v simulation for both gas (aid liquid phases. The relative baffles was accounted for through the movement of the rotating impeller to the static baffles 'improved inner-outer iterative algorithm. The spatial discretization of the governing equations was performed on a cylindrical staggered grid. For the LES, a conventional Sniagorinsky,v sub-grid model was adapted to modeling the turbulence of the liquid phase. The momentum and continuity equations were discretized using the finite diffrence method, ",ij'h a third order QUICK (Quadratic Upwind Interpolation tor Convective Kinematics) scheme used for convective terms. The phase-resolved predictions of the LES were compared with the experimental data and the simulation results by the standard k-epsilon model, suggesting that the LES has much better accuracy than the k-epsilon model. (c) 2008 American Institute of Chemical Engineers.

[1]  Vivek V. Ranade,et al.  A COMPUTATIONAL SNAPSHOT OF GAS-LIQUID FLOW IN BAFFLED STIRRED REACTORS , 1994 .

[2]  F. Mashayek,et al.  Development and validation of a multi-block flow solver for large eddy simulation of turbulent flows in complex geometries , 2004 .

[3]  K. Squires,et al.  Large eddy simulation of turbulent gas-solid flows in a vertical channel and evaluation of second-order models , 1998 .

[4]  Vivek V. Ranade,et al.  Gas–liquid flow generated by a Rushton turbine in stirred vessel: CARPT/CT measurements and CFD simulations , 2005 .

[5]  Zai-Sha Mao,et al.  Experimental and numerical study of gas hold-up in surface aerated stirred tanks , 2006 .

[6]  George Papadakis,et al.  Large Eddy Simulation of Turbulent Flow in a Rushton Impeller Stirred Reactor with Sliding-Deforming Mesh Methodology , 2004 .

[7]  P. Sagaut.  Large Eddy Simulation for Incompressible Flows , 2001 .

[8]  G. L. Lane,et al.  Modelling of the Interaction between Gas and Liquid in Stirred Vessels , 2000 .

[9]  Zai-Sha Mao,et al.  Experimental and Numerical Investigation on Gas Holdup and Flooding in an Aerated Stirred Tank with Rushton Impeller , 2006 .

[10]  G. Evans,et al.  Numerical modelling of gas-liquid flow in stirred tanks , 2005 .

[11]  Catherine Xuereb,et al.  Gas−Liquid Flow Generated by a Pitched-Blade Turbine: Particle Image Velocimetry Measurements and Computational Fluid Dynamics Simulations , 2003 .

[12]  A. Brucato,et al.  Particle drag coefficients in turbulent fluids , 1998 .

[13]  Vivek V. Ranade,et al.  Gas–liquid flow in stirred reactors: Trailing vortices and gas accumulation behind impeller blades , 1999 .

[14]  J. Smagorinsky,et al.  GENERAL CIRCULATION EXPERIMENTS WITH THE PRIMITIVE EQUATIONS , 1963 .

[15]  Bjørn H. Hjertager,et al.  Computational fluid dynamics simulation of bioreactors , 1995 .

[16]  Jos Derksen,et al.  Large eddy simulations on the flow driven by a Rushton turbine , 1999 .

[17]  P. Moin,et al.  LES of atomizing spray with stochastic modeling of secondary breakup , 2002 .

[18]  F. Mashayek,et al.  Modeling subgrid-scale effects on particles by approximate deconvolution , 2005 .

[19]  Chao Yang,et al.  Large eddy simulation of liquid flow in a stirred tank with improved inner-outer iterative algorithm , 2006 .

[20]  J. Eggels,et al.  Direct and large-eddy simulation of turbulent fluid flow using the lattice-Boltzmann scheme , 1996 .

[21]  Laszlo Fuchs,et al.  Large eddy simulation of flow in stirred vessels , 2002 .

[22]  Wei-Ming Lu,et al.  Local gas holdup, mean liquid velocity and turbulence in an aerated stirred tank using hot-film anemometry , 1987 .

[23]  Ying Liao,et al.  Large Eddy simulations of a stirred tank using the lattice Boltzmann method on a nonuniform grid , 2002 .

[24]  A. D. Gosman,et al.  Multidimensional modeling of turbulent two‐phase flows in stirred vessels , 1992 .

[25]  Geoffrey M. Evans,et al.  Predicting gas–liquid flow in a mechanically stirred tank , 2002 .

[26]  Bjørn H. Hjertager,et al.  LDA measurements and CFD modelling of gas-liquid flow in a stirred vessel , 1996 .

[27]  Khellil Sefiane,et al.  Experimental investigation of self-induced thermocapillary convection for an evaporating meniscus in capillary tubes using micro-PIV , 2005 .

[28]  Tron Solberg,et al.  Large eddy simulation of the Gas-Liquid flow in a square cross-sectioned bubble column , 2001 .

[29]  Alberto Brucato,et al.  Large-eddy simulation of turbulent flow in an unbaffled stirred tank driven by a Rushton turbine , 2005 .

[30]  J. Derksen.  Numerical Simulation of Solids Suspension in a Stirred Tank , 2003 .