基于自主设计的同轴撞击流反应器,运用计算机流体力学(CFD)数值模拟技术对内管开孔进行了优化设计.首先通过单因素试验确定了反应液在内外管入口处的速度比例,在此基础上,分别以开孔排数N、内管轴向孔间距L、内管径向开孔个数n及开孔直径D为试验因素,设计正交试验.对每组试验进行数值模拟,以距入口顶端不同距离处微孔的速度均方根差为评价指标,得到内管开孔的优化设计方案为:反应器内管沿轴向均匀开设6排微孔,每排微孔间距为12mm,径向均匀开设5个微孔,孔径均为0.5mm.基于正交试验的优化结果,对模型进行重新定义并对其环形微通道反应区内的流场结构进行数值模拟分析,结果表明:开孔处产生的撞击束均有较高的速度梯度,并且反应液在环形微通道反应区内发生强烈撞击,并发生充分混合与反应,实现了内管开孔的最优化设计.%Based on the self-designed coaxial impinging stream reactor,the present study optimized the inner tube openings by applying CFD numerical simulation technology. Firstly,the velocity scale of raw material solution in the tube inside and outside the entrance were determined by a single-factor experiment,and then orthogonal test was designed based on perforated row numberN,inner tube axial spacingL,the number of radial holes inn and hole diameterD these four test factors respectively. Each set of experiments was designed by numerical simulation,and with micro-holes at different distances from the entrance to the top Speed root-mean-square deviation of evaluation index,the optimization design of inner tube openings was obtained,in which reactor tube evenly along the axial opens 6 micro-holes,with each micro-hole spacing 12mm. Radial direction opens 5 micro-pores evenly,with the aperture of 0.5mm. Based on orthogonal test of optimization results,the model was redefined and circular micro-flow structure within the reaction zone was analyzed by numerical simulation. The results showed that the bombarding beam had a higher velocity gradient and reaction fluid in annularmicro- reaction zone not only collide with each other violently,but also they were fully mixed. Finally, this study achieved the optimal design of the inner tube opening.
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