Ross LPD型静态混合器内湍流传热与混合强化特性  

Turbulent heat transfer and mixing enhancement characteristics in Ross LPD static mixer

作　　者：孟辉波[1,2] 蒙彤 禹言芳[1,2] 王宗勇[1,2] 吴剑华[1,2] MENG Huibo;MENG Tong;YU Yanfang;WANG Zongyong;WU Jianhua(School of Mechanical and Power Engineering,Shenyang University of Chemical Technology,Shenyang 110142,Liaoning,China;Liaoning Key Laboratory of Chemical Technology for Efficient Mixing,Shenyang University of Chemical Technology,Shenyang 110142,Liaoning,China)

机构地区：[1]沈阳化工大学机械与动力工程学院,辽宁沈阳110142 [2]沈阳化工大学辽宁省高效化工混合技术重点实验室,辽宁沈阳110142

出　　处：《化工学报》2022年第8期3541-3552,共12页CIESC Journal

基　　金：辽宁特聘教授计划项目(辽教函[2018]35号);国家自然科学基金项目(21476142);辽宁省教育厅高等学校基本科研项目重点项目(LJKZ0429);辽宁省“百千万人才工程”项目(201892151);辽宁省自然科学基金项目(2022-MS-290,2019-ZD-0082);沈阳市中青年科技创新人才计划项目(RC200032)。

摘　　要：在湍流状态Re=2640~17600下,采用恒热通量传热实验与数值模拟相结合的方法,系统研究Reynolds数Re和交错角对Ross LPD型静态混合器内湍流流动与传热性能影响,采用Nusselt数、Darcy摩擦系数、综合传热系数、速度场与温度梯度和压力梯度协同角等参数评价混合器内传热强化性能;基于CFD与LPT相耦合分析混合器内流体微元拉伸率。研究结果表明:SST k-ω模型预测Ross型静态混合器湍流阻力及传热结果与实验结果具有很好一致性;Ross混合器流场内形成与流场尺度较为接近的纵向涡,其涡心在圆形截面与半圆形截面中心间周期性迁移,横截面内湍流分散混合效率是Kenics的3.36~1.72倍;当Re>7040时,Ross LPD综合传热性能明显优于KSM;当叶片夹角为30°时,综合传热性能系数具有最大值;Ross LPD内插件具有高效低阻的技术优势和结构改进潜力。The performance of turbulent flow and heat transfer in Ross low pressure drop(LPD) static mixer were experimentally and numerically investigated under constant heat flux condition. The effects of Reynolds number Re and staggered angle were evaluated in the turbulent state with a range of Re from 2640 to 17600. The Nusselt number, Darcy friction coefficient, comprehensive heat transfer coefficient, and synergistic angle between velocity field and temperature/pressure gradient were used to evaluate the heat transfer enhancement performance in the mixer. The stretching characteristics of fluid element in the Ross LPD and Kenics static mixers were analyzed based on computational fluid dynamics(CFD) and Lagrangian particle tracking(LPT) method. The results show that the performance of turbulent resistance and heat transfer in Ross static mixer predicted by SST k-ω model was in good agreement with experimental results. A longitudinal vortex with the similar scale of the flow field is induced in the Ross mixer, and its vortex center shifts periodically between the centers of circular and semicircular sections. The average stretching rate in the cross section of Ross static mixer is 3.36—1.72 times that in Kenics mixer which indicates that the enhancement ability of dispersion micromixing efficiency gradually weakens with the increasing axial length. The comprehensive heat transfer performance of Ross LPD gradually becomes much better with the increase of Re. Furthermore, it is obvious larger than 1 which indicates that η is superior to that in the KSM when Re>7040. When the blade angle is 30°, the comprehensive heat transfer coefficient of performance has the maximum value. The Ross LPD internal inserts have the technical advantages of high efficiency with low flow resistance and the potential for structural improvement.

关 键 词：静态混合器 混合 传热 综合传热性能系数 场协同 

分 类 号：TK124[动力工程及工程热物理—工程热物理]