螺旋槽管强化传热数值模拟及其场协同分析

Numerical simulation of heat transfer in spiral groove pipe and its field synergy analysis

利用Fluent软件分别对光管、单头螺旋槽管及双头螺旋槽管传热及管内流动情况进行模拟,得到了湍流状态下管内流场分布云图,并从场协同理论出发,分析了螺旋槽管强化传热机理.仿真结果显示,在低雷诺数条件下,螺旋槽使管内产生较多的二次流,速度在横截面上的分量增加,努塞尔数保持为光管的1.6-2.2倍,换热性能优于光管,并且双头螺旋槽管的换热性能要优于单头螺旋槽管.但随着雷诺数的增加,场协同角逐渐接近90°,努塞尔数增加趋势变缓,换热性能增加量变缓,而且当雷诺数较高时,螺旋槽管的阻力系数急剧上升,换热性能不及光管.

Utilizing the software of FLUENT to simulate the flow fields and heat transfer of light pipe,single-headed spiral groove pipe and double-headed spiral groove pipe respectively,the distributions of velocity and pressure in the state of turbulence are obtained;and the mechanism of heat transfer enhancement of spiral groove pipe is discussed based on field synergy theory.Simulation results show that the spiral groove produces secondary flow and makes velocity component increase is on the cross-section,the average Nuis 1.6to 2.2times,the heat transfer performance of spiral groove pipe is superior to light pipe under low Reynolds numbers;and the heat transfer performance of double-headed spiral groove pipe is superior to single-headed spiral groove pipe.But with the increase of Reynolds numbers,the field synergy angle approaches 90°;the NUheat transfer performance increase is slowed down;and the resistance coefficient of spiral grooved tube has risen sharply when Reynolds number（Re）is high;the heat transfer performance become worse.