气液双相微纳米气泡发生器的关键结构优化分析

Optimization Analysis of Key Structure of Gas-Liquid Two-Phase Micro-Nano Bubble Generator

为了对气液双相微纳米气泡发生器的关键结构进行优化分析,建立了该发生器的三维模型并分析了其工作原理,利用有限元仿真软件FLUENT对该发生器流场在不同工作压力下进行数值模拟仿真,分析仿真结果发现:当发生器的入口压力为1.5MPa时产生的气泡数量最多,在入口压力分别为0.5、1.0、1.5和2.0MPa时,该发生器产生直径在1 nm左右的气泡所占比例分别为41.9%、53.3%、73.2%和69.6%;探讨了该发生器通流腔直径、扩张腔大/小径、旋流腔直径4个关键结构的尺寸对产生的气泡大小和数量的影响,并分析了产生相关影响的原因。结果表明:当入口压力为1.5 MPa时,该微纳米气泡发生器产生的微纳米气泡数量最多,粒径最均匀;适当提高通流腔直径和旋流腔直径有利于提高该微纳米气泡发生器的工作性能,而改变扩张腔小径和扩张腔大径对于提高其性能均无显著的影响。

In order to optimize the key structure of a gas-liquid two-phase micro-nano bubble generator,a three-dimensional model of the generator was established and its principle was analyzed.The finite element simulation software FLUENT was used to simulate the flow field of the generator under different working pressures.The simulation results show that,when the inlet pressure is 1.5 MPa,the generator can generate the largest number of bubbles.When the inlet pressure is 0.5,1.0,1.5 and 2.0 MPa,respectively,the proportion of bubbles with diameters around 1 nm is 41.9%,53.3%,73.2% and 69.6% respectively.The influence of the size of 4 key structures,the diameter of flow chamber,the large/small diameter of the expansion chamber and the diameter of the swirl chamber on the diameter and quantity of the bubble was explored,and the reason of the related influence was analyzed.The results show that,when the inlet pressure is 1.5 MPa,the micro-nano bubble generator produces the largest number of micro-nano bubbles and the most uniform particle size.Appropriately increasing the diameter of flow chamber and the diameter of the swirl chamber is beneficial for the performance of the micro-nano bubble ge-nerator,and changing the large/small diameter of the expansion chamber has no significant effect on improving its performance.