Abstract
In this paper a model is described for calculating the gas-liquid flow in stirred vessels. The general fluid flow code FLUENT is used for calculating the single-phase flow pattern. This flow pattern is used as input for an in-house code named GHOST! which calculates the distribution of the gas over the vessel on the basis of balance equations. A mathematical model for bubble break-up and bubble-coalescence, based on local turbulence intensity and local energy dissipation rate, is incorporated in this code. Details regarding modelling the impeller, bubble coalescence and bubble break-up are given in the paper. The GHOST! code is capable of calculating local void fraction, local bubble size, local interfacial area and local mass transfer. These local values can be integrated to yield the overall gas holdup and the overall mass transfer rate. There is a good agreement between computational results and measurements. Based on the simulations, it is concluded that full homogeneity of the gas-liquid mixture will never be achieved. This knowledge should be used in the optimization process.
Original language | English |
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Pages (from-to) | 594-606 |
Number of pages | 13 |
Journal | Chemical Engineering Research and Design |
Volume | 72 |
Issue number | A4 |
Publication status | Published - Jul 1994 |
Externally published | Yes |