在螺旋管中流动的流体，会在离心力的作用下形成二次流，它一方面能够增强管内的交混流动，进而增强换热；另一方面也会带来能量的耗散，增大流阻。本研究以高温气冷堆蒸汽发生器螺旋传热管为对象，探讨此特定结构形式下二次流现象对单相、两相流动和换热的的影响，并结合数值模拟分析其演变规律与相关机理。本研究在建立单根螺旋管单相、过冷沸腾和饱和沸腾的计算流体力学（CFD）FLUENT模型基础上，利用实验数据验证了模型的有效性；进而研究几何参数（曲率比、螺距）、边界条件（热边界条件、入口雷诺数、壁面热流等）对单相、两相段二次流现象的影响，以及表征流动换热特性重要指标参数的变化规律；最后应用本CFD模型探讨了高温堆HTR-PM蒸汽发生器螺旋管几何参数下的换热规律及二次流现象的影响，揭示了CFD模型与工程设计所使用经验公式的区别与联系，并拟合了局部Nu数公式。通过本文研究发现：标准、RNG、Realizable 模型、RSM模型均可以较好地实现对单相段的模拟，Eulerian两相流模型结合RPI沸腾模型以及RSM湍流模型，可以较好地实现对于过冷沸腾和饱和沸腾段的模拟。在单相段，螺距增大、曲率比增大、雷诺数增加均能降低迪恩涡的完整性和对称性，壁面压力梯度、二次流速度、切应力也会随着曲率比和雷诺数的增大而增大，但几乎不随螺距变化，壁面周向压力梯度和切应力分布均服从内侧低，外侧高的V型分布；受二次流影响，壁面平均传热系数变化规律也随曲率比和雷诺数的增加而增大，截面局部换热系数也呈现内侧低的V型分布。在两相段，螺距、盘管直径减小，螺旋管直径增大均能降低迪恩涡的完整性和对称性，但两相段迪恩涡的完整性和大小会随着入口雷诺数的增加而增大；曲率比增加能够在一定程度上使壁面压力梯度、二次流速度以及切应力有所增加，增强管内流动换热；由于两相段存在汽相，扩大了服从U型分布的内侧压力梯度和低切应力区域的范围，局部换热系数与切应力分布类似；迪恩涡能促进液相从高含汽率区向低含汽率区转移，迪恩涡的完整性、大小、对称性与二次流强度和换热能力非正相关。

The fluid flowing in a helix tube will form a secondary flow under the action of centrifugal force, which on the one hand can enhance the cross-mixing flow in the tube and thus heat transfer; on the other hand, it will also bring about energy dissipation and increase the flow resistance. In this study, the effect of secondary flow phenomenon on single-phase and two-phase flow and heat transfer in this specific structure is investigated in the context of a spiral heat transfer tube of a high temperature gas-cooled reactor steam generator, and its evolution and related mechanism are analyzed by numerical simulation.In this study, based on the computational fluid dynamics (CFD) FLUENT model for single-phase, subcooled boiling and saturated boiling of a single spiral tube, the validity of the model is verified by using experimental data; then the effects of geometric parameters (curvature ratio, pitch) and boundary conditions (thermal boundary conditions, inlet Reynolds number, wall heat flow, etc.) on the secondary flow phenomena in single-phase and two-phase sections are investigated, as well as the changes in the parameters characterizing the heat transfer characteristics of the flow. The variation law of important index parameters; finally, this CFD model is applied to explore the heat transfer law and the effect of secondary flow phenomenon under the geometrical parameters of the spiral tube of the high temperature reactor HTR-PM steam generator, revealing the difference and connection between the CFD model and the empirical formula used in engineering design, and fitting the local Nu number formula.It is found that the standard model, RNG model, Realizable model, and RSM models can simulate the single-phase section well, and the Eulerian two-phase flow model combined with the RPI boiling model and RSM turbulence model can simulate the subcooled boiling and saturated boiling sections well. In the single-phase section, increasing the pitch, curvature ratio and Reynolds number can reduce the integrity and symmetry of the Dean vortex, and the wall pressure gradient, secondary flow velocity and shear stress also increase with the increase of curvature ratio and Reynolds number, but they almost do not change with the pitch, and the wall circumferential pressure gradient and shear stress distribution obey the V-shaped distribution of low inside and high outside; influenced by the secondary flow, the variation pattern of the average heat transfer coefficient at the wall The average heat transfer coefficient of the wall also increases with the increase of curvature ratio and Reynolds number, and the local heat transfer coefficient of the cross section also shows a V-shaped distribution with low inner side. In the two-phase section, the decrease of pitch and coil diameter and the increase of spiral tube diameter can reduce the integrity and symmetry of the Dean vortex, but the integrity and size of the Dean vortex in the two-phase section will increase with the increase of inlet Reynolds number; the increase of curvature ratio can increase the wall pressure gradient, secondary flow velocity and shear stress to a certain extent, and enhance the heat transfer in the tube; due to the existence of the vapor phase in the two-phase section, it enlarges the inner pressure gradient obeying the U-shaped Due to the presence of vapor phase in the two-phase section, the range of the inner pressure gradient and low shear stress region that obeys U-shaped distribution is expanded, and the distribution of local heat transfer coefficient is similar with wall shear; the Dean vortex can promote the transfer of liquid phase from the high vapor content region to the low vapor content region, and the integrity, size and symmetry of the Dean vortex are no longer positively correlated with the secondary flow strength and heat transfer capacity.