液态锂型中子转换靶若干关键问题研究

项目名称： 液态锂型中子转换靶若干关键问题研究

项目编号： No.11305005

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 数理科学和化学

项目作者： 高原

作者单位： 北京大学

项目金额： 30万元

中文摘要： 中子核科学在放射性同位素生产、中子物理、核能材料研究、核安全领域研究具有重要应用。加速器中子源可以产生具有一定能谱的中子。由于实验中往往需要较高的中子通量，因此要求带电粒子束具备较高的流强。束流能量较高时，高功率的束流轰击小面积靶，其功率密度将达几百kW/cm^2，这对靶的抗负载能力提出了极高的要求。液态锂由于具有良好的中子学性能、抗辐照性能和传热性能，是目前中子液态靶材并兼做冷却剂的主要候选材料。本课题针对液态锂中子转换靶的研究现状，主要围绕加速器中子源高功率中子转换靶中液态锂自由液面形态，强流离子束与自由液面相互作用，热力学分布等问题展开模拟和实验研究,构建理论模型，对无窗靶件内部自由界面的形态和特性进行数值模拟，模拟不同流速，锂喷嘴和导向板尺寸等参数下，液态锂的流体形貌，表面稳定性，从而为未来高功率中子转换靶的研制提供更多的理论指导和数据基础。

中文关键词： 高功率；液态锂中子转换靶；自由液面流体；热沉积；数值模拟

英文摘要： There are many applications of neutron in radioactive isotopes, neutron reactions and material research for nuclear energy systems. The neutron source could be drove by intensity ion accelerator. Ion beam with high power will be used to bombard converter target to generate neutrons. In the driver LINAC, to achieve the high neutron flux, there will be very large energy deposition density (hundreds kW/cm2) loading on the small area of the target. One of the challenges is to develop a target that withstands such extreme thermal loads from powerful ion beam bombardment. Liquid lithium technology has been proposed to solve this problem in accelerator driven neutron converter target station. The liquid lithium target is good alternative due to its preferable nuclearand thermal properties. In our project, some issues about the liquid lithium target will be researched. Calculations were performed to obtain the shape of free surface of flowing liquid lithium, the influence of target components such as nozzle to the free surface, the interaction of the high power ion beam and the free surface of liquid lithium, the heat distribution of target.The results will be used to support the design of windowless target toensure the formation of a stabIe free surface with desirabIe shape.

英文关键词： high power；liquid lithium neutron converter target；free surface flown；heat deposition；numerical simulation