Abstract:

Because of the advantages of high heat transfer and mixing efficiency, the ultrafine particles with small particle size, uniform and narrow distribution range can be prepared by opposed confined impinging jets reactor. The effect of jet velocity and structure size on micromixing quality was investigated by using iodide-iodate parallel-competitive reactions. Micromixing efficiency was compared with that of the mixing chamber size by the same proportion to one time. The experimental results show that the segregation index decreases with jet velocity increases, so that micromixing quality enhances. The increasing of nozzle distance to nozzle diameter ratio results increasing of segregation index, and micromixing efficiency decreases. As mixing chamber height and outlet size increases, segregation index first increases and then reduces. The effect of mixing chamber height on micromixing efficiency is more significant than that of mixing chamber outlet size. The value of the segregation index in magnifying opposed confined impinging jets reactor is 2.4 times larger than that of original opposed confined impinging jets reactor, it demonstrates the significant decreasing of micromixing quality. The results can provide efficient and safe technical support for the preparation of nanocomposite energy-containing materials.

Key words: energy-containing materials, opposed confined impinging jets reactor, micromixing, segregation index, ultrafine particles

摘要：

由于对置受限式撞击流反应器较高的传热及混合效率，能够制备出粒径小、均匀且分布范围窄的超细颗粒。本文采用碘化物-碘酸盐平行竞争反应体系研究入射速度、结构尺寸对对置受限式撞击流反应器微观混合效果的影响规律，并将混合腔尺寸同等比例放大一倍进行对比研究。结果表明，随着入射速度的增大，离集指数减小，微观混合效果提高。喷嘴间距与喷嘴直径比的增大使得离集指数增大，微观混合效果降低。离集指数随着混合腔高度、混合腔出口尺寸的增大呈现先增大后减小的趋势，且混合腔高度对混合效果的影响较混合腔出口尺寸显著。将对置受限式撞击流反应器混合腔尺寸扩大一倍，离集指数增加到原来的2.4倍，微观混合效果显著下降，但是在较大入射速度下，两种结构的混合效果差距减小。研究结果可为纳米复合含能材料的制备提供高效、安全的技术支持。

关键词: 含能材料, 对置受限式撞击流反应器, 微观混合, 离集指数, 超细颗粒