Qianxu Wang, Yuanlai Xie, Huihui Hong, Yang Zhu, Fang Wang, Kun Tian, Bin Li
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引用次数: 0
摘要
作为负离子中性束注入器(NNBI)的重要组成部分,低温泵主要为束流的产生和传输提供合适的真空环境。本文建立了两个低温泵的液氮(LN2)管道结构模型,并进行了模拟和实验研究。利用 Ansys 稳态热分析软件对热辐射屏蔽挡板(LN2 冷却)进行了热分析,同时利用 Fluent 对 LN2 管道中的两相流动进行了模拟,然后对两种管道结构的压降、温度、速度、气相体积分数等参数进行了分析和比较。模拟结果表明,优化后的结构 B 可使压降降低 3 bar,结构 A 的出口温度为 78.8 K,结构 B 的出口温度为 79.2 K,温差为 0.4 K,出口速度从结构 A 的 2.067 m/s 增加到 4.实验结果表明,结构 A 的出口温度为 79.4 K,而结构 B 的出口温度为 80.1 K,优化后的结构 B 可减少压降约 3 bar。
Analysis and optimization of LN2 two-phase flow in CRAFT NNBI cryopump
As an important component of Negative ion based Neutral Beam Injector (NNBI), the cryopump mainly provides a suitable vacuum environment for beam generation and transmission. In the paper, Liquid nitrogen (LN2) pipe structure models of two cryopumps were established for simulation and experimental studies. Thermal analysis of the thermal radiation shielding baffle (LN2 cooling) was carried out by Ansys steady-state thermal analysis software, while Fluent was used to simulate the two-phase flow in the LN2 pipeline, then the pressure drops, temperature, velocity, gas-phase volume fraction, and other parameters of the two pipeline structures were analyzed and compared. The simulation results show that the optimized structure B can reduce the pressure drop by 3 bar, the outlet temperature of structure A is 78.8 K, the outlet temperature of structure B is 79.2 K, the temperature difference is 0.4 K. The outlet velocity increases from 2.067 m/s to 4.947 m/s for Structure A, and from 1.096 m/s to 6.614 m/s for Structure B. The experiment results show that the outlet temperature of structure A is 79.4 K, meanwhile the outlet temperature of structure B is 80.1 K, the optimized structure B can reduce the pressure drop about 3 bar.
期刊介绍:
Nuclear Engineering and Technology (NET), an international journal of the Korean Nuclear Society (KNS), publishes peer-reviewed papers on original research, ideas and developments in all areas of the field of nuclear science and technology. NET bimonthly publishes original articles, reviews, and technical notes. The journal is listed in the Science Citation Index Expanded (SCIE) of Thomson Reuters.
NET covers all fields for peaceful utilization of nuclear energy and radiation as follows:
1) Reactor Physics
2) Thermal Hydraulics
3) Nuclear Safety
4) Nuclear I&C
5) Nuclear Physics, Fusion, and Laser Technology
6) Nuclear Fuel Cycle and Radioactive Waste Management
7) Nuclear Fuel and Reactor Materials
8) Radiation Application
9) Radiation Protection
10) Nuclear Structural Analysis and Plant Management & Maintenance
11) Nuclear Policy, Economics, and Human Resource Development