导叶式旋流器内油滴的聚结破碎及影响因素

Droplet coalescence and breakup and its influence factors in vane-guided hydrocyclone

利用流场测试实验和模拟计算对导叶式旋流器的内部流场和湍流性能进行研究,得到导致旋流场中油滴发生聚结破碎现象的内因为时均速度梯度引起的黏性剪切力和湍流流动引起的高剪切应力及湍动能,并分析了油滴破碎的主要发生部位。同时为宏观考察导叶式旋流器内油滴聚结与破碎相对作用强弱,验证了旋流器的分离性能作为表征量的可行性,并在此基础上,利用导叶式旋流器的分离性能实验结果对油滴聚结破碎发生的外因进行研究,结果表明导向叶片的结构参数(叶片数和叶片出口角)和旋流器的操作参数(入口流速、溢流率、分散相入口浓度和操作温度)均会影响到油滴在旋流器中的存在和运动形态。

Simulations and experiments on the flow field were used to study the internal flow and turbulence in a vane-guided hydrocyclone.The main factors resulting in droplet coalescence and breakup are viscous shear force related to the velocity gradient and the high shear stress and turbulent kinetic energy in the turbulence.Moreover,the positions in the hydrocyclone where droplets inclined to coalesce and break were investigated.In order to understand the relative importance of droplet coalescence and breakup in the vane-guided hydrocyclone,the separation performance as its characteristic was verified.The experiments on the separation performance also show that the structural parameters,such as the number and outlet angle of guided vanes,and operating parameters,such as the inlet velocity,split ratio,inlet concentration and operating temperature,affect the droplet coalescence and breakup in the vane-guided hydrocyclone.