黏弹性流体环空内脉动层流流动的理论解析

摘要

结合运动方程和本构方程,建立同心环空内上随体Maxwell型黏弹性流体在周期性压力梯度作用下脉动层流流动的数学模型,采用固有函数法对模型进行理论求解,得到环空内的速度分布,并讨论各种因素对环空内速度分布的影响.结果表明:受周期性压力梯度作用的影响,环空内的速度随时间呈周期性变化；流体的弹性作用使环空内的速度剖面具有显著区别于牛顿流体的特征.%By combining the momentum equation and the constitutive equation, a mathematical model for the pulsating laminar flow of the upper-convected Maxwell viscoelastic fluid under periodic pressure gradient in concentric annuli was set up. The velocity profile was obtained by using the intrinsic function method and the factors influencing the velocity profile were discussed. The results show that the velocity in annuli changes periodically with time due to the periodic pressure gradient. Fluid elasticity is responsible for the difference of velocity profile for Newtonian fluid and non-Newtonian fluid.