Abstract: Impinging stream reactors have been widely applied in industry with the advantages of efficient mass transfer and strong interaction between phases. Based on the traditional impinging stream reactor, a novel two-way accelerating tube coaxial opposing impinging stream reactor was constructed. The flow field mixing characteristics simulation was carried out in the reactor with air as the continuous phase and liquid water as the discrete phase. The high-speed gas?liquid mixed flow process at different gas flow rates was analyzed. Moreover, the changes of velocity, pressure distribution, particle diameter and stagnation time in the internal flow field were explored. The results showed that the flow field distribution was symmetrical above the impact surface, and the pressure and velocity at the stagnation point fluctuated most violently. With the increase of initial gas phase velocity, the flow field velocity rose slowly, then decreased slowly, and finally decreased sharply, and the pressure in the flow field decreased slowly, then increased slowly, after increased sharply and gradually coincided in the form of the double peaks of M-type. In addition, the pressure value at stagnation point increased non-linearly. When the initial gas velocity uout=30 m/s and uin=15 m/s, the velocity and pressure gradient of impact region were the largest, the turbulent kinetic energy was the strongest. Furthermore, the average diameter of the droplets in the new reactor was smaller and the residence time was longer, which were obviously superior to traditional reactor.

Key words: gas-liquid impinging stream reactor, mixing, numerical simulation, velocity and pressure distribution, particle diameter distribution

摘要： 撞击流反应器具有高效传质和相间强相互作用等优点，在工业上被广泛应用。基于传统撞击流反应器构建了新型二路加速管同轴对置撞击流反应器，进行了以空气为连续相、液态水为离散相的流场混合特性模拟，分析了不同气相流速下气液高速混合流动过程，研究内部流场速度、压力分布及颗粒直径与停滞时间的变化特性。结果表明，流场分布关于撞击面对称，且驻点处压力、速度波动最剧烈。随初始气相速度增加，流场速度呈先平缓上升再缓慢下降，后急剧下降的趋势；流场压力呈先平缓下降再缓慢上升再急速上升，以M型双波峰逐渐趋于重合的趋势，且驻点处压力值非线性增加。当气相初始速度uout =30 m/s, uin =15 m/s时，撞击区域的速度梯度与压力梯度最大，湍动能最强；液滴在反应器中的平均直径最小、滞留时间较长，且明显优于传统反应器。

关键词: 气液相撞击流反应器, 混合, 数值模拟, 速度与压力分布, 粒径分布