摘要
采用CFD方法对燃料组件进行过冷流动沸腾数值模拟研究是反应堆热工水力分析的一项重要内容。本研究使用STAR-CCM+基于欧拉双流体模型结合壁面沸腾模型对管内过冷流动沸腾进行数值模拟,得到了壁面温度、主流温度及空泡份额的分布。基于实验结果对网格模型、湍流模型、壁面沸腾模型及相间作用力模型的参数设置进行了敏感性分析。研究结果表明,对于欧拉双流体模型,并非网格量越多结果越准确,加热面第1层网格的高度对结果影响显著。湍流模型和曳力模型对计算结果影响较小,非曳力中的湍流耗散力及升力对结果影响较大。Li Quan或Hibiki-Ishii汽化核心密度模型与Kocamustafaogullari气泡脱离直径模型组合对壁面温度及空泡份额的计算较准确。本研究可为反应堆燃料组件内过冷流动沸腾数值模拟提供参考依据。
The critical heat flux is essential to the operational safety of nuclear power plants, and it plays a vital role in the thermal-hydraulic and structural design of a fuel assembly. To improve the heat transfer efficiency of the reactor fuel assembly, it is necessary to accurately calculate the two-phase flow boiling characteristics and the critical heat flux in the fuel assembly. Accurate simulation of subcooled flow boiling in simple geometry(such as round tubes, annular tubes, and rectangular channels) can lay a foundation for the research of boiling crisis phenomenon in complex structures(such as fuel rod bundle). Compared with single-phase flow, mass, momentum, and energy transfer process occur at the interface of two-phase flow. In addition to the conventional turbulence model and grid model, the interactions between liquid and vapor phases need to be characterized by various interphase forces. Furthermore, the wall boiling model is needed to describe the distribution of heat flux at the heating surface, which includes several empirical auxiliary models. Accurate simulation of flow boiling phenomenon requires the further study of many sub-models in numerical calculations. In this study, the commercial computational fluid dynamics package STAR-CCM+ based on the Eulerian two-fluid model combined the wall boiling model was used to simulate the subcooled flow boiling in a vertical tube, and obtain the distribution of wall temperature, mainstream temperature and void fraction. Based on the experimental results, the sensitivity analysis of the parameter settings of the grid models, turbulence models, boiling models and interphase force models was carried out. The results demonstrate that for Eulerian two-fluid model, with the increase of the number of grids, the results are not more accurate. The height of the first layer of grid on the heating surface has a significant effect on the calculations. By setting different first layer grid heights for comparison, it is found that when the grid height is low enough to ma
作者
尚泽敏
杨立新
袁小菲
刘伟
刘余
蒋汀岚
SHANG Zemin;YANG Lixin;YUAN Xiaofei;LIU Wei;LIU Yu;JIANG Tinglan(School of Mechanical,Electronic and Control Engineering,Beijing Jiaotong University,Beijing 100044,China;Science and Technology on Reactor System Design Technology Laboratory,Nuclear Power Institute of China,Chengdu 610213,China)
出处
《原子能科学技术》
EI
CAS
CSCD
北大核心
2022年第3期457-466,共10页
Atomic Energy Science and Technology
关键词
欧拉双流体模型
壁面沸腾模型
过冷流动沸腾
计算流体力学
Eulerian two-fluid model
wall boiling model
subcooled flow boiling
computational fluid dynamics
