基于Fluent软件建立了正弦型波纹管内流体的数值分析模型,研究了湍流状态下管内流体的流动与传热特性,分析了波纹管不同结构参数及流体进口速度对管内强化传热性能的影响规律。研究表明:当雷诺数Re相同时,正弦型波纹管内流体的平均努赛尔数Nu是其当量直径光管的1.65~2.67倍,且当Re约为28 000时,传热效果最佳;波高、波长对波纹管强化传热均有较大影响,在高雷诺数条件下,经过结构优化的波纹管能使回流区与主流区交界处形成不稳定的剪切层,此时传热效果达到最优。
The flow and heat transfer performances of water in sinusoidal corrugated tubes under turbulent state were numerically investigated by Fluent software,and the influences of inlet velocity and tube structure parameters on heat transfer performance were analyzed. It was revealed that the mean Nusselt number( Nu) in the corrugated tube was about 1. 65-2. 67 times as much as that in the straight tube with the same equivalent diameter,and the best enhancing heat transfer performance was obtained when the Reynolds number( Re) equaled about 28 000. The wave height and the periodical length of corrugated tube had significant influence on heat transfer results. Under the condition of the high Reynolds number,the heat transfer performance would be the best one when the unstable shearing boundary layer formed at the junction between the backflow zone and the main stream zone.