| Packed columns have been broadly applied in the industry because of the high throughput, excellent separation efficiency, low pressure drop, great operation flexibility, small liquid holding. Actual experimental means can't measure the velocity, concentration and the diameter of liquid drop (or air bubble) in gas-liquid two phase system. so it is urgent to study the flow of liquid in theory for optimizing design of packed columns and expanding the application field of filling. With the appearance and development of CFD, many scholars have begun to study gas-liquid two phase flow. On the basis of multiphase flow theory, the paper takes standard k-ε model as turbulent model, Euler-Lagrange model as multiphase model. The flow of gas-liquid two phase in twin-tangential annular distributor was simulated through CFD soft FLUENT. In this paper,, not only analysis with the change of flow field in the distributor but also analysis of maldistribution factor (M_t ), foam carrying rate (e% ), pressure drop (△p ), turbulent kinetic energy ( ), and turbulent dissipation rate (ε) are carried out to characterize the performance of gas distributor through keeping the charge of dispersed phase uniform and changing the charge of primary phase. The results indicate: 1,The change of gas flow field in the distributor is consistent in the case of two-phase feeding and single-phase feeding. The models chosen can simulate the movement, concentration, diameter of liquid drop in the two-phase system. 2,Maldistribution of gas falls with increasing of the charge of gas in the gas-liquid system. 3,Entrainment is very small (0.034%~0.13%) and increases with the increasing of the charge of gas. 4,Turbulent kinetic energy is the greatest in the inlet of distributor and on the front 2 baffles in the distributor, where the pulsant velocity changes quickly and grads is big.
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