自吸式文丘里洗涤器运动特性及强化机理的模拟研究

文丘里洗涤器具有传质效率高、无需额外动力及设备尺寸小等优点,在危险化学品洗消、工业除尘等领域有着广泛应用,为了分析文丘里洗涤器内的气液运动规律获得强化机理,利用CFD构建三维模型,分析了非浸没式文丘里喉部气速、浸没高度、喉部间距等典型操作参数对文丘里内部流场、分散效果以及引射性能的影响。发现受气体剪切的作用,进入文丘里洗涤器内部的液体主要贴壁运动,只有少部分被分散形成雾滴。引射量随入口速度的增加而增加,当入口气速增加至18.4 m/s时,引射量增加了5倍,从0.11 kg/s增加到0.53 kg/s。引射量随浸没高度的降低和喉部间距的增大而降低,喉部间距的增加,降低了液膜在管壁附着量,增加了在文丘里洗涤器中间的分布,提高了气-液体的碰撞概率。此外,也发现挡板分布器的加入,降低了液体的贴壁量,增加了液体组分的均匀性,提高了气液接触的概率。

Simulation Study on Motion Characteristics and Strengthening Mechanism of Self Suction Venturi Scrubber

Venturi scrubbers were widely applied in hazardous chemical decontamination and industrial dust removal fields as they had advantages of simple structure,high efficiency and convenient operation.In order to analyze the law of gas-liquid movement in Venturi scrubber and obtain the enhancement mechanism,a three-dimensional model was built by CFD.The effects of typical operating parameters such as gas velocity,immersion height and throat spacing on the internal flow field,dispersion effect and injection performance of Venturi were analyzed.It was found that under the action of gas shear,the liquid entering the venture scrubber mainly adheres to the wall,and only a small part was dispersed to form droplets.When the inlet gas velocity increased to 18.4 m/s,the injection volume increased five times,from 0.11 kg/s to 0.53 kg/s.With the decrease of immersion height and the increase of throat spacing,the amount of liquid film adhering to the pipe wall was reduced.The distribution in the middle of Venturi scrubber was increased.The probability of gas-liquid collision was increased.In addition,it was also found that the addition of baffle distributor reduces the amount of liquid adhering to the wall,increased the uniformity of liquid components,and improves the probability of gas-liquid contact.