Numerical Algorithm for Studying Hydrodynamics in a Chemical Reactor with a Mixer

Abstract

The mixing in stirred vessels is acknowledged to be one of the most important characteristics for many industrial technologies. So that research in this area has concentrated for a long time on visual flow studies and on the measurements of overall properties such as power consumption, the overall gas holdup and overall mass transfer rate. Although, some features of the flow regimes inside the vessels can be obtained in this way. Mathematical modeling of the mixing processes recently becomes a useful and effective method for investigation.

This paper presents a mathematical model for hydrodynamics in a cylindrical reactor with one Rashton mixer. The liquid is supposed to be incompressible and the process 2D steady state. The Navier- Stokes equations are described by means of the stream-function and vorticity.

A numerical methodology for simulating mixing processes in stirred vessels is also presented. The numerical algorithm for solving these equations is based on an alternating direction implicit method for irregular mesh. The proposed algorithm is tested for different model tasks. The initial numerical results for hydrodynamics are presented graphically.