相对流速对非球形铝滴旋转受力的影响

Influence of relative velocity on the force of non-spherical rotating aluminum droplet

针对固体火箭发动机中非球形铝滴的旋转受力问题进行数值模拟,详细分析流速变化对颗粒的受力影响。计算结果表明,非球颗粒在流场中的升力系数与无量纲转速之间已经不再满足经典的理论关系式。雷诺数Re<1时,周向升力系数存在着交替出现的2组极大值与极小值;升力系数均为正值,且周向变化较为平缓。随来流速度增加,阻力系数变得均衡,系数值向0值逼近;升力系数也急速降低。当相对流速由0.5 m/s提高到5 m/s时,颗粒所受阻力锐降89%。颗粒的阻力系数与雷诺数之间满足新的关系式。

The rotation characteristics of non-sphere aluminum in different kinds of fluid velocity were simulated in order to an-alyze the effect of flow rate on the forces acting on particles. Results show that, the relationship between lift coefficient and dimen-sionless rotational speed doesn＇t obey the typical law. When Reynolds number is less than 1, two groups of maximum and minimum values appear alternately on certain circumferential location for drag coefficient. Lift coefficient is always positive and smooth. With the increasing of the inflow velocity, drag coefficient becomes even, and the value is approaching to zero, while the lift coefficient falls quickly. If the relative velocity increase from 0.5 m/s to 5 m/s, drag coefficient of the droplet decreases by 89% sharply. Drag coefficient and Reynolds number obey a new law.