关键词: 气液两相流, 分配, 数值模拟, 相分离, 控制, 临界流

Abstract: A novel distributor consisting of a swirl vane, nozzles and fluid splitting rooms was proposed to distribute gas-liquid two-phase flow evenly. The swirl van was used to change upstream flow patterns into annular flow with uniform film thickness to make sure all the nozzles have same inlet condition and the nozzles were used to accelerate the gas-liquid mixture to achieve critical flow. In order to investigate the distributor behavior under different extraction ratios, a 2-nozzle and a 4-nozzle distributor were designed. A numerical model was developed to simulate the gas and liquid velocity vector distribution in the distributor. The simulation results showed that all the nozzles had similar flow behavior if their outlet pressures were equal. Experiments were conducted in an air-water two-phase flow loop, with the distributor horizontally installed. Superficial gas velocity varied from 5.0 m·s^-1 to 25.0 m·s^-1, liquid superficial velocity was in the range of 0.012-0.14 m·s^-1. The flow patterns observed during the tests included wavy flow, annular flow and slug flow. It was found that gas and liquid splitting ratio was determined by the number of the nozzles and was independent of flow patterns, gas and liquid superficial velocity and resistance characteristic of the downstream pipeline. The splitting ratios of the 2-nozzle and 4-nozzle distributors were 0.5 and 0.25 respectively.

Key words: gas-liquid flow, distribution, numerical simulation, phase splitting, control, critical flow