摘要
从受力分析的角度,对气泡运动方程进行了推导,并对半径在40～350μm之间的微小气泡进行了仿真计算。结果表明,当考虑气泡上浮的加速过程时,气泡上浮速度明显小于未考虑加速过程时的值,其变化范围为5～10%。因此,对于短距离气泡上浮过程,必须考虑气泡上浮过程中由加速度引起的虚拟质量力和Basset力对上浮速度的影响。在此基础上对气泡运动方程进行了详细分析,结果表明,阻力系数与粘滞系数是影响气泡上浮速度的主要因素,它们的取值与上浮速度成反比,并得出了通用的阻力系数表达式。
The equation of bubble motion and its simulation results with the bubble radius of 40-350um is obtained in this paper by analyzing the forces acting on bubbles in still water. It turns out that the terminal rise velocities, when considering speedup in rising, decrease by 5-10%, apparently much less compared with the value without considering speedup. So, the effects of added mass force and Basset force on the rise velocities must be introduced when considering a short-distance bubble rising in some experiments. By analyzing the equation of bubble motion, another important result is obtained that the drag coefficient and the dynamic viscosity of liquid are important when calculating the rise velocity of bubble. After detailed analysis of the two factors, it is found that they were reverse to the terminal velocities, and, in addition, a general expression of drag coefficient is obtained.
出处
《舰船电子工程》
2009年第4期155-158,共4页
Ship Electronic Engineering
