利用CFD模拟方法,研究了液液喷射混合器中引射流体进料角度的影响行为和优化选择问题。选择7种不同引射角度为考察对象,考察了喷射器内部流体的流动特性与掺混效果。结果表明:不恰当的引射角度将导致引射流体在喷嘴外围环隙的速度和流量分配不均,进而导致流场偏移;随着引射角度的增加,压力降、喷射系数、混合段流体速度和湍流耗散率呈现出先增大后减小的变化趋势;不同引射角度下流体达到混合完全所需要的距离相同,但是质量分数存在差别。综合分析,在7种引射角中,引射流体的最佳引射角度为60°,此条件下喷射器内混合段流体速度大,喷射系数高,混合效果好,同时对管壁的冲击力小。
The optimum selection and effect behavior of liquid-liquid ejector at different suction angles were investigated based on Computational Fluid Dynamics(CFD) simulation.Seven suction angles were selected for comparison and the hydrodynamics and mixing characteristics of the internal flow field were analyzed.The results showed that improper suction angles caused the different velocity and flow distribution of suction fluid at outer ring gap of nozzle and the deflection of the flow field.The pressure drop and the liquid entrainment ratio increased at first then represented opposite variation trend which decreased with the increase of the suction angles as well as velocity at mixing section and turbulent dissipation rate.The distance was the same when the fluid got totally mixed at different suction angles while the mass fraction was different.To sum up,60° was the best suction angle,at which the velocity at mixing section is maximum,the liquid entrainment ratio is the highest,the mixing behavior is the best and the impact on the wall is minimum among the seven angles.