【摘要】 撞击流混合器是一种新型的微观混合器,今研究了T型直流对撞(IS)、锥形对撞(CIS)、直流旋撞(VS)和二次旋流旋撞(TVS)四种结构的撞击流混合器的微观混合性能。然后以Villermauxu/Dushman快速平行竞争反应测定混合器的离集指数Xs,并考察了流体流速、流体流速比和混合器结构对离集指数的影响。混合器混合效果用离集指数来衡量,离集指数越小混合效果越好。结果表明:其余工艺条件相同的情况下,流体流速越大,离集指数Xs愈小;两股流体流速比越小,离集指数Xs愈小;喷嘴进口管道直径越小,离集指数Xs愈小。锥形的比直线形的、旋流比直接撞击流混合效果要好,而且旋流使物料在混合器中的停留时间延长;根据实验数据模拟计算,T形撞击流微混合器的微观混合时间在1 ms数量级;用Fluent 6.2.1商业软件模拟计算了混合器内的流场分布情况,发现模拟计算结果和实验结果基本吻合。更多还原

【Abstract】 The impinging streams mixer is a new type micromixer.The micromixing characteristics of the mixers with T-shaped impinging streams,conical impinging streams,vortex streams and twice vortex streams were investigated,respectively.The micromixing performance of the mixers was expressed with the segregation index(Xs);and the smaller the Xs is,the better the micromixing effects are.The Villermauxu/ Dushman fast parallel competing reaction was used to quantitatively determine the segregation index(Xs) in the above four different mixers;and the effects of flow rate,volumetric flow ratio and mixer configuration on the micromixing performance were studied.The experimental results show that the Xs decreases with increasing the flow rate,while increases with the increase of both the volumetric flow ratio and the inlet diameter of the nozzles.The conical impinging streams mixer has better micromixing capability than that of the line-type impinging streams mixer,and the vortex occurred results in the decreasing Xs and prolonging the resident time of the reactants.According to the simulation calculation,it was found that,in the impinging streams mixers,the micromixing time is about 1 ms.The flow field distributions of the micromixers were calculated by using Fluent 6.2.1 software,and the simulated results are consistent with the experimental results.更多还原