Abstract In a Dual Coolant Lead Lithium (DCLL) blanket, flow channel insert (FCI) with low electrical conductivity and low thermal conductivity is introduced to reduce the MHD pressure drop and improve the heat transfer efficiency. In the present work, we aim at performing a direct simulation of the magneto-thermal-fluid-structure multi-physical fields in a typical poloidal duct with different electrical conductivities of FCI, using a coupled computing platform including CFD and the finite element method (FEM), to study the pressure field, velocity field, temperature field, as well as the deformation and stresses of FCI. A consistent and conservative scheme and PISO method on an unstructured collocated mesh are employed to solve the incompressible Navier–Stokes equations with the Lorentz force included. The results show that: with the increasing of FCI's electrical conductivity (σFCI), the pressure reduction efficiency becomes lower; the pressure difference between the FCI's inside patches and the corresponding outside patches increases after an initial reducing; two jets appear in the side gap and the one near FCI develops to a reverse flow; the variation of the temperature difference across FCI and the interface temperature of first wall (FW) is non-monotonic; the cause of nonlinear variation of thermal deformations and stresses of FCI with electrical conductivity results from the nonlinear effect of Lorentz force on the liquid metal velocity. This work is the theoretical basis of blanket design.

中文翻译：

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FCI 电导率对 DCLL 毯中 MHD 流动的非线性影响

摘要 在双冷却铅锂（DCLL）毯中，引入了低导电率和低导热率的流道嵌件（FCI）以降低MHD压降并提高传热效率。在目前的工作中，我们的目标是使用包括 CFD 和有限元方法的耦合计算平台，对具有不同 FCI 电导率的典型极向管道中的磁-热-流体-结构多物理场进行直接模拟。 FEM），研究压力场、速度场、温度场，以及 FCI 的变形和应力。在非结构化并置网格上采用一致和保守的方案和 PISO 方法来求解包含洛伦兹力的不可压缩 Navier-Stokes 方程。结果表明：随着FCI的电导率（σFCI）的增加，减压效率变低；FCI 的内部补丁和相应的外部补丁之间的压力差在初始减小后增加；侧隙中出现两股射流，靠近 FCI 的一股发展为反向流动；FCI 两端的温差和第一壁的界面温度 (FW) 的变化是非单调的；FCI 热变形和应力随电导率非线性变化的原因是洛伦兹力对液态金属速度的非线性影响。这项工作是毯子设计的理论基础。s 内部补丁和相应的外部补丁在初始减少后增加；侧隙中出现两股射流，靠近 FCI 的一股发展为反向流动；FCI 两端的温差和第一壁的界面温度 (FW) 的变化是非单调的；FCI 热变形和应力随电导率非线性变化的原因是洛伦兹力对液态金属速度的非线性影响。这项工作是毯子设计的理论基础。s 内部补丁和相应的外部补丁在初始减少后增加；侧隙中出现两股射流，靠近 FCI 的一股发展为反向流动；FCI 两端的温差和第一壁的界面温度 (FW) 的变化是非单调的；FCI 热变形和应力随电导率非线性变化的原因是洛伦兹力对液态金属速度的非线性影响。这项工作是毯子设计的理论基础。FCI 热变形和应力随电导率非线性变化的原因是洛伦兹力对液态金属速度的非线性影响。这项工作是毯子设计的理论基础。FCI 热变形和应力随电导率非线性变化的原因是洛伦兹力对液态金属速度的非线性影响。这项工作是毯子设计的理论基础。