【作者】 孙铭；

【导师】 陈长琦； 欧阳峥嵘；

【作者基本信息】 合肥工业大学 ， 制冷及低温工程， 2006， 硕士

【摘要】 中性束注入(NBI)加热是托卡马克(Tokamak)装置中等离子体的三种常用加热方法之一，它具有原理简单、输入功率高等优点，已成为一些大型核聚变装置主要的加热手段。为了尽可能减少从中性化室出来的中性粒子束的再电离，必须保持连接到托卡马克装置的漂移管道具有动态高真空。为此，在NBI系统漂移管道内放置了一台液氦低温冷凝泵，以冷凝束流中的氢及氢的同位素来保持动态高真空。 本文对中国科学院等离子体物理研究所中性束注入系统作了简要介绍，对漂移管道低温阵列所受到的热负荷进行了分析，并建立了数学模型，经数值计算得到了“人”字型挡板与液氦冷凝板温度呈二维分布的规律。通过对低温阵列的ANSYS模拟，绘出了“人”字型挡板与液氦冷凝板的温度场呈梯度分布图；最后进行了漂移管道的真空与低温性能实验，验证了漂移管道低温阵列能够满足托卡马克实验对等离子体中性束注入(NBI)加热的要求。更多还原

【Abstract】 Neutral beam injection (NBI) is one of three kinds of commonly used plasma heating methods on Tokamak. It has the advantage of simple principle and high power input, and it has become the main heating method in some large-scale nuclear fusion equipment. In order to reduce the re-ionization of neutral particle beam that come out from the neutralization chamber as far as possible, the dynamic vacuum within the drift pipe connected to Tokamak must be maintained highly. Therefore, a low temperature liquid helium vapour pump has been laid within the drift pipe of the NBI system to maintain continual vacuum by using the condensation of hydrogen and its isotope in the beam. This pump is situated within the drift pipe between the main vacuum chamber of the neutral beam injector and Tokamak.This article briefly introduces the neutral beam injection system in Institute of Plasma Physics, Chinese Academy of Sciences, and makes the analysis and computation that aimed at the heat load the cold pump endured when it worked. A numerical solution of the cold plate is also obtained. Through ANSYS simulation for the low temperature matrix of the cold pump, a reliable temperature field distribution map is also drawn. Finally, by taking the experiment as the basis, the vacuum and low temperature condition in the drift pipe is examined to determine whether it can satisfy the request of Tokamak experiment.更多还原