螺旋槽管脉冲流强化对流换热数值及场协同分析

Numerical analysis on convection heat transfer in spirally fluted and field synergy analysis

通过数值模拟计算研究了在螺旋槽管内通入脉冲流后的强化换热机理.数值计算结果表明,脉冲流动能引起出口压力呈周期波动,波动幅度随脉冲流频率的增大而增大;脉冲流动能够使流体在螺旋槽管管壁附近产生漩涡,并出现周期性的生成、漂移和脱落;由于漩涡的作用,增强了流体的径向扰动和相对扰动;脉冲流动能够改善速度场与温度梯度场之间的协同程度,从而起到强化传热的效果.

By numerical simulation computation,enhanced heat transfer mechanism in spirally fluted tubes was researched under passing pulsating flow condition.Numerical result shows that pulsating flow can cause the outlet pressure to fluctuate cyclical and the extent of fluctuation increases with the pulsating flow frequency.The pulse flowing can make the fluid generate the whirlpool nearby the spirally fluted tubes and the phenomenon of periodic production,drift,and fall-off appears.Because of the vortex,the fluid motion and relative motion are enhanced.The pulse flowing can improve the coordination level between velocity and temperature,which,therefore,had strengthened the heat transfer effect.