利用流体力学软件FLUENT对波纹管与扭带结合时的流场及传热进行了数值模拟，结合场协同原理考察了不同结构参数和操作参数对流动和传热的影响。结果表明：在入口雷诺数5000~60000，内插扭带波纹管由于扭带的螺旋导流作用，使壁面边界层减薄，在流动区域形成漩涡产生二次流，强化了对流传热过程；插入扭带后的波纹管内的流动仍具有周期性的特点，压降比普通的波纹管增加了2~3倍，且扭率较小时压降较高；场协同角在管子入口处较小，随流动的进行逐渐增大并趋于稳定；协同角随入口速度的增大呈递增趋势；有扭带的波纹管较光管协同角减小了约10%，较普通波纹管减小了约2%，场协同程度随扭率减小而增强。%The object of the study is using CFD software FLUENT to numerically analyze the flow and heat transfer characteristics of bellows with twisted tape inserts within a Reynolds number range of 5000-60000. The convective heat transfer enhancement with different structurals and operating parameters were also investigated by combining field synergy principle. The results show that the velocity boundary layer is thinner and vortexes appear in the vicinity of the twisted tape due to its spiral effect. The secondary flows in the flow regime contribute to the convective heat transfer performance. The periodic flow is also found in bellows with twisted tape inserts. However, its pressure drop is 2~3 times higher than ordinary bellows, and the pressure drop increases with the decrease of twist ratio. The average intersection angle is small at the entrance, and it increases with the development of flow and then becomes stable. The average intersection angle also increases with the increase of entrance velocity. Compared with smooth tubes and normal bellows, the average intersection angle of bellows with twisted tape inserts decreases by about 10% and 2%, respectively, and the field synergy degree increases with the decrease of twist ratio.
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