结合有限体积法和有限元法研究U型流道中磁流体的流动特性、传热性能和流道插件的力学性能,发现外加磁场强度、金属流体进口速度以及流道插件导电性能对流道内速度场、温度场及流道插件应力、应变场的影响规律。计算结果表明:当外加磁场增强,出口段流场的温度也相应升高;较高的进口速度可以提高出口段流体的温度;提高流道插件导电性能,速度场将呈现“M”型分布,但出口段温度场变化极小。流道插件危险区域位于过渡段侧壁附近,该处应力随磁场增强而增大,随进口速度升高而降低,随流道插件电导率增大略有提升,但都小于插件材料的许用应力。本工作可为ITER包层的设计提供有价值的参考。
In the fusion reactor blanket module, a U-shaped channel was investigated. Numerical simulations based on the finite volume method and finite element method were carried out to study magnetohydrodynamic features, heat transfer, and structure mechanical behaviors. The influences caused by flow velocity, magnetic field strength, and structural electrical conductivity were considered. Results suggest that stronger magnetic field and higher inlet velocity lead to higher outlet fluid temperature. With larger flow channel insert conductivity, ‘M-shaped’ velocity profiles were observed. Considering structural thermal stresses, the most dangerous area is near the side wall in the bend segment. Thermal deformation of the flow channel insert increases with the magnetic field magnitude, and thermal stresses decrease with the increase of inlet velocity. The electrical conductivity has little effect on structural stresses and strains. This work provides valuable information for the design of blanket modules.
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