内插自振弹簧换热管脉冲流强化换热数值分析

摘要

针对脉冲流影响内置弹簧换热管换热效果的问题,运用计算流体动力学技术模拟研究了在内置弹簧换热管中分别通入稳态流和不同参数脉冲流情况下的换热情况,得到了不同情形下的管内温度场和压力场.研究结果表明:通入脉冲流后,内插自振弹簧换热管出口平均压力呈现与脉冲流周期相同的正(余)弦波动,且波动振幅随着脉冲流频率的增大而增大.相对于通入稳态流而言,通入脉冲流时的速度边界层厚度减小,从而增大了强化传热系数.管内对流传热系数随着振幅的增大而增大,但频率对传热系数的影响却很小.%The effect of pulse flow on the performance of heat exchange tube with built-in spring was investigated using software FLUENT. The temperature field and the pressure field under different pulse flow were obtained. Results indicate that the average export pressure shows the same vibration period with that of pulse flow and the fluctuation amplitude increases with the increment of the frequency of pulse flow; comparing with the case of steady flow, the thickness of velocity boundary layer decreases significantly and thus the heat transfer coefficient is enhanced greatly; the vibration amplitude of pulse flow has great effect on the heat transfer enhancement, while the frequency of pulse flow shows little influence on the heat transfer enhancement.