振荡管流换热的解析解及强化换热特性

经求解随时间正弦变化的非定常压力梯度下，管内流体振荡时的运动方程和能量方程，得到了振荡管流换热的速度场、温度场以及当量导温系数的解析解,通过分析可知，影响管内振荡流轴向换热的无量纲参数主要有：无量纲振荡频率，无量纲振幅和流体普朗特数,其中，无量纲振荡频率直接影响流动的速度分布，且随着无量纲振荡频率增加，强化换热效果增强,随着无量纲振幅的增大，管内流动有效导热面积增加，等温面法向温度梯度也增加，使得强化换热效果增强,强化换热效果同样也随流体普朗特数的增加而增强。

Theoretical solution on heat transfer in oscillatory pipe flow and analysis of enhanced heat transfer

By solving the momentum and energy equations of the oscillatory flow driven by a sinusoidally varying pressure gradient,the general analytical solutions of the velocity profile,the temperature profile and the enhanced thermal diffusivity were obtained.Based upon the analytical solutions,it is found that three parameters influenced the enhanced heat transfer for the problem are the dimensionless oscillatory frequency,the dimensionless amplitude and the Prandtl number of the fluid.The velocity profile is directly determined by the dimensionless oscillatory frequency,and the enhanced thermal diffusivity increases with the increase of dimensionless oscillatory frequency,dimensionless amplitude and Prandtl number.