【摘要】 通过选用欧拉-欧拉多相流模型和RNGκ-ε湍流模型对文丘里除尘器流动特性进行了数值模拟,为文丘里除尘器的结构优化提供依据。在74 m/s的喉管气速下比较喷嘴位置和喷嘴液体速度对文丘里除尘器性能的影响。结果表明,喷嘴位置对文丘里除尘器的压力降及喉管处的液体分布影响较大,当喉管气速和液体入射速度不变时,压力降随喷嘴位置后移而增加,而当喷嘴位置位于中部时喉管内的液体分布较为均匀。更多还原

【Abstract】 The present paper is aimed to make a simulated study for the effects of the position of orifice on the fluid dynamics of the Venturi scrubber as well as on the pressure drop and the liquid distribution by using an ANSYS Fluent 14. 5 software of the RNGκ-ε turbulence model and the Euler-Euler multiphase model,for the fluid dynamics of the Venturi scrubber is the principal indicator of the performance of the said scrubbers. For the research purpose,we have developed a computational mesh via the software ANSYS ICEM in terms of the dimensions and other geometric features of the device. The chief computational domains of the device include the exit,the entry ducts of the device in hoping to get rid of the unreal turbulence in the liquid jet due to the entrance effects. The mesh was refined near the liquid injection orifices. The pressure-velocity coupling can be solved with the phase coupled SIMPLE algorithm with the convergence criteria for all the problem variables being kept at 10-4and with the relaxation parameters kept within the range of 0. 2-0. 4. At the same time,we have made a comparison between the performance and the fluid dynamics of the Venturi scrubber under the three different orifice positions and the different liquid rates,whereas the liquid distribution has been studied under the throat gas velocity of 74 m / s and the liquid velocity of 7. 5 m / s and 12. 5 m / s. The results of our simulated study indicate that the Euler-Euler multiphase model can help to predict the fluid dynamic status-in-situ of the scrubber as well. Moreover,the velocity and turbulent kinetic energy distribution has also been found uniform when the orifice remains at the middle position. Therefore,it can be deduced that the location of the orifice tends to have a great impact on the liquid distribution in the Venturi scrubber throat,which may account for the difference of the liquid and gas velocity,implying that the gas velocity tends to increase with the decrease of the flow area and retrogress of the orifice along the Venturi scrubber on the condition that the liquid velocity remains constant. In such a situation,little difference can be found with the gas and liquid velocity when the orifice is in the front position,which may lead to the distribution of the liquid towards the center of the Venturi scrubber throat,and,then,vice versa. The pressure drop can thus be found increasing with the increase of the liquid velocity and the backward movement of the orifice,whereas the liquid distribution remains uniform with the pressure drop being moderate on the condition of 74 m / s gas velocity,and that of the liquid velocity being 7. 5 m / s in the middle orifice position.更多还原