基于场协同原理的涡发生器强化撞击流反应器混合性能分析

Analysis of Mixing Performance of Impinging Stream Reactor Enhanced by Vortex Generator Based on Field Synergy Theory

为了提高撞击流反应器的混合性能,采用数值模拟的方法分析了置入矩形翼涡发生器后撞击流反应器内的流场特性与混合特性,并且优化了矩形翼涡发生器参数。研究了矩形翼涡发生器尺寸参数与位置参数对撞击流反应器混合强度的影响,以及涡发生器位置参数对反应器内速度分布和湍动能分布的影响,运用传质场协同原理分析了设置矩形翼涡发生器和未设置矩形翼涡发生器的撞击流反应器内速度场和浓度场的协同性。结果表明,随着径向间距r的增加混合强度呈现出先增后减的趋势,当翼宽h、转轴间距d和迎流攻角β逐渐增加时混合强度波动变化,在矩形翼涡发生器的翼宽h=10 mm,转轴间距d=8 mm,径向间距r=30 mm,迎流攻角β=30°时,反应器内混合强度最大,得到的混合效果最佳;在两股流体充分撞击的情况下,撞击流反应器内径向射流区域的速度分布呈现为“双峰”分布规律,涡发生器位置参数的改变可以提高径向速度,在转轴间距d=8 mm、迎流攻角β=30°时径向速度最高,反应器内径向射流区域的湍动能分布呈现出“单峰”分布规律,但涡发生器位置参数的变化对于湍动能分布的影响不大;从场协同的角度分析可知,矩形翼涡发生器的加入改变了撞击流反应器内径向射流的速度大小和方向,进而改善了撞击流反应器内速度场与浓度场的协同性,提高了撞击流反应器的混合性能。

The flow field characteristics and mixing characteristics of an impinging stream reactor equipped with a rectangular wing vortex generator are analyzed using the numerical simulation method to improve the mixing performance of an impinging stream reactor.The parameters of the rectangular wing vortex generator are optimized.The effects of size and position parameters of the rectangular wing vortex generator on the mixing strength of the impinging stream reactor and the effects of position parameters on velocity distribution and turbulent kinetic energy distribution in the reactor are investigated.The mass transfer field synergy principle is applied to analyze the synergy between velocity and concentration fields in the impinging stream reactor,both with and without the rectangular wing vortex generators.The results showed that the mixing strength initially increases and decreases with rising radial spacing,r.The mixing strength fluctuation changes as the wing width,h,rotor spacing,d,and attack angle,β,increase gradually.When the wing width h=10 mm,rotor spacing d=8 mm,radial spacing r=30 mm,and attack angleβ=30°for the rectangular wing vortex generator,the mixing strength in the reactor is at its highest,and the mixing effect is optimal.Under conditions of full impact from two flows,the velocity distribution in the radial jet region of the impinging flow reactor follows a"bimodal"distribution pattern.Adjusting the vortex generator position parameters improves the radial velocity,with the highest radial velocity occurring when the axial spacing d=8 mm and the attack angleβ=30°.The turbulent kinetic energy distribution in the radial jet region of the reactor exhibits a“singlepeak”distribution,although changes in the vortex generator position parameters have minimal effect on the turbulent kinetic energy distribution.From the perspective of field synergy,adding a rectangular wing vortex generator alters the magnitude and direction of the radial jet velocity in the impinging stream reactor.As a result,the synergy between the velocity and concentration fields improves,enhancing the mixing performance of the impinging stream reactor.