利用计算流体力学软件对内管为螺纹管的螺旋套管换热器壳程流体的湍流流动和换热性能进行了数值模拟。通过与内管为光管的研究结果对比，揭示了内管为螺纹管时壳程流体的速度场和温度场分布，研究了雷诺数、槽高对壳程流体湍流流动及换热性能的影响，并利用场协同原理初步揭示了螺纹复合螺旋流动强化流体换热的机理。结果表明，螺纹内管的螺纹凸起对螺旋套管换热器壳程流体的扰流和导流作用明显，在研究范围内(Re=10 000~24 000)，内管为螺纹管的螺旋套管换热器壳程流体的传热效率较内管为光管的模型最大提高了22.1%；结构参数相同时，随着Re增大，螺旋套管换热器壳程流体的Nu逐渐增大，阻力系数f逐渐减小，综合评价因子Ψ逐渐减小，在研究范围内，Nu最大增加了85.6，f最大减少了0.008，Ψ从1.35减小至1.18。当Re一定时，当量高度h'增大，f逐渐增大，Nu先增大后减小。由场协同原理分析得出，h'=0.220时，在螺纹凸起扰流和导流的作用下壳程流体的温度场与速度场协同性能较好，综合评价因子Ψ最大，螺纹的优化当量高度h'宜取约0.220。

In this work, computational fluid dynamics software was used to numerically simulate the turbulent flow and heat transfer performance of the shell side fluid of the spiral casing heat exchanger with a threaded tube. The effect of Reynolds number and groove height on the turbulent flow and heat transfer performance of the shell side fluid was investigated. The field synergy principle was used to reveal the mechanism of fluid heat transfer enhancement by thread compound spiral flow. The results showed that the thread protrusions of the threaded inner tube had a significant effect on the disturbance and conduction of shell side fluid of the spiral casing heat exchanger, and the heat transfer efficiency of the shell side fluid of the spiral casing heat exchanger with the inner tube as a threaded tube was up to 22.1% higher than that of the model with the inner tube as a smooth tube. When the structural parameters were the same, with the increase of Reynolds number, Nusselt number of the shell side fluid of the spiral casing heat exchanger gradually increased, flow resistance gradually decreased, and the comprehensive evaluation factor ψ gradually decreased. Within the scope of the research, Nusselt number increased by 85.6, flow resistance decreased by 0.008, and the comprehensive evaluation factor ψ decreased from 1.35 to 1.18. When Reynolds number was certain, the equivalent height h' increased, flow resistance gradually increased, and Nusselt number first increased and then decreased. According to the analysis of field synergy principle, when the equivalent height h' was 0.220, the temperature field and velocity field synergy performance of the shell side fluid was better under the action of thread protrusion disturbance and diversion, and the comprehensive evaluation factor ψ was the largest. The optimal equivalent height h' of the thread should be about 0.220.