以水和煤油为研究体系,利用数值模拟方法研究了标准挡板(Standard Baffle, SB)、标准穿流挡板(Standard Punched Baffle, SPB)和之字形穿流挡板(Zigzag Punched Baffle, ZPB)搅拌槽内液-液分散特性。结果表明,采用之字形穿流挡板可有效降低搅拌槽内挡板后方的死区。随着搅拌转速增加,三种挡板搅拌槽的搅拌功耗逐渐增大,煤油液滴直径逐渐减小。在相同搅拌转速下,之字形穿流挡板搅拌槽内液滴直径均小于标准挡板和标准穿流挡板。随着搅拌转速增加,ZPB和SPB搅拌槽内的液滴直径与SB搅拌槽的差距均呈现先增大后减小的趋势,当搅拌转速为400 r/min时,差异最大。此时,相较于SB搅拌槽,SPB和ZPB搅拌槽内液滴直径分别减小18.16%和36.87%。
Baffle is an important part of the stirred tank, and it can effectively improve the flow state of fluid and the effective utilization of power in the stirred tank. In order to reduce power consumption and improve mixing performance of the stirred tank, a zigzag punched baffle has been developed in our previous work. However, its performance in a liquid-liquid stirred tank has not been performed. With taking water and kerosene as a research system, the liquid-liquid dispersion characteristics in stirred tanks with standard baffles (SB), standard punched baffles (SPB), and zigzag punched baffles (ZPB) were studied by numerical simulation. The results showed that due to the formation of the impinging steam, the zigzag punched baffle can effectively reduce the dead zone behind the baffle in the stirred tank. With an increase of stirring speed, the stirring power consumption of the three different baffled stirred tanks all gradually increased, meanwhile the kerosene droplet diameter decreased. At the same stirring speed, the power consumption of the SPB stirred tank was almost the same as that of the SB stirred tank, while the gap between ZPB and SB stirred tanks was growing with the increase of stirring speed. The droplet diameter in the stirred tank with zigzag baffle was much smaller than that of the tanks with standard baffle and the standard punched baffle at the same stirring speed. With the increase of stirring speed, the difference between the droplet diameter of ZPB and SPB and that of SB increased first and then decreased. When the stirring speed is 400 r/min, the difference was the largest. At this time, compared with the SB stirred tank, the droplet diameter of kerosene in the SPB and ZPB stirred tanks decreased by 18.16% and 36.87%, respectively.