浮力作用下聚变堆液态金属包层内磁流体流动与传热特性研究

In liquid metal fusion blanket, the non-uniform volumetric heat deposited by the fusion neutrons lead to the non-uniform density distribution of liquid metal, these will cause buoyant flows and mix flow , in the fusion blanket where the magnetic field is very high and the Hartmann number is very large, these effect caused by the buoyancy will significantly influence the flow and heat transfer characteristics. In this project, based on the background of liquid metal fusion blanket, a numerical method will be studied and developed for the calculaiton of magnetohydrodynamic flow in the blanket under the influnce of buoyancy force. Considering the fusion magentic field and non-uniform volumetric heating, the flow and heat transfer characteristics will be studied numerically, the pressure drop, velocity fields and temperature fields influenced by the buoyancy force will be analyzed, the relationship of the dimensionless parameters such as Grashof number, Hartmann number and Reynolds number will be discussed,and the effect of this parameters on the flow and heat transfer will be studied. This project will make a distinct comprehension on the mechanism of MHD flow and heat transfer under the influence of buoyancy force, and will provide suggestion for the optimizing the thermal-hydraulic and structure design of liquid metal blanket,

在聚变堆液态金属包层中，由于聚变中子在包层内核热沉积不均匀，引起了液态金属冷却剂不均匀的密度分布，密度差产生的浮力导致包层流道内形成自然对流及混合对流，特别是在聚变堆强磁场高哈特曼数条件下，这种效应将严重影响包层内液态金属的流动及传热特性。本项目拟以液态金属包层为研究背景，以大规模数值模拟为主要手段，研究聚变堆强磁场及非均匀的聚变中子核热沉积环境下，液态金属流体在包层多物理场耦合环境下的流动及传热特性，分析浮力及电磁力作用下金属流体流动压降、流动速度场及传热特点，各重要无量纲数对流动、传热、及包层结构的影响，丰富对浮力作用下包层内磁流体流动理论的认识和理解，为液态锂铅包层的结构设计优化和热工水力学参数设计优化提供理论指导和实验依据。

在聚变堆液态金属包层中，由于聚变中子在包层内核热沉积不均匀，引起了液态金属冷却剂不均匀的密度分布，密度差产生的浮力导致包层流道内形成自然对流及混合对流，特别是在聚变堆强磁场高哈特曼数条件下，这种效应将严重影响包层内液态金属的流动及传热特性。本项目以聚变堆液态金属包层存在的关键问题之一—浮力作用下的MHD流动传热为背景，研究包含浮力源项的高Hartmann数MHD数值模型与计算方法，开发并验证了适用于聚变堆液态包层高Hartmann数工况的MHD分析程序MTC，并针对MHD湍流特征开发出适用于聚变堆液态包层工况的湍流模型，探索了液态包层的MHD浮力效应机理和规律，对典型单冷包层概念SLL和双冷包层概念DLL进行了浮力效应分析，分析结果完善了浮力作用下包层内磁流体流动理论和传热机制的认识和理解，为液态金属包层的结构和热工水力学设计优化提供了重要指导依据。