Fluid Flow Modeling of a Gas-induced Pulsating Flow Bubble Column
نویسندگان
چکیده
A three-dimensional (3D) Euler-Euler gas-liquid two-phase mathematical model was developed for simulating the local transient fluid flow in a gas-induced pulsating flow bubble column using computational fluid dynamic (CFD) method, with multiple size group (MUSIG) model implemented to predict the bubble size distribution. Model simulated results such as local transient axial liquid velocities and time-averaged liquid turbulent kinetic energy distributions were validated successfully by corresponding experimental measurements under varied operating conditions, i.e. pulsating amplitudes and frequencies. It was found that the liquid turbulent kinetic energy increased with the increase in pulsating amplitude and frequency, and a maximum value appeared at an axial position of Z = 0.4 m, centerline of the column. Furthermore, local transient fluid flow characters such as the gas holdups, gas velocity fields and liquid velocity fields, as well as bubble size distributions were predicted reasonably by the proposed model.
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