原子能科学技术 ›› 2021, Vol. 55 ›› Issue (2): 229-236.DOI: 10.7538/yzk.2020.youxian.0166

• 反应堆工程 • 上一篇    下一篇

竖直下降两相流相界面结构输运特性

乔守旭;钟文义;谭思超;张彪;王爽   

  1. 哈尔滨工程大学 黑龙江省核动力装置性能与设备重点实验室,黑龙江 哈尔滨150001; 哈尔滨工程大学 核安全与先进核能技术工信部重点实验室,黑龙江 哈尔滨150001
  • 出版日期:2021-02-20 发布日期:2021-02-20

Transport Characteristic of Interfacial Structure for Vertical-downward Two-phase Flow

QIAO Shouxu;ZHONG Wenyi;TAN Sichao*;ZHANG Biao;WANG Shuang   

  1. Heilongjiang Provincial Key Laboratory of Nuclear Power System & Equipment, Harbin Engineering University, Harbin 150001, China;Key Laboratory of Nuclear Safety and Advanced Nuclear Energy Technology, Ministry of Industry and Information Technology, Harbin Engineering University, Harbin 150001, China
  • Online:2021-02-20 Published:2021-02-20

摘要:

竖直下降两相流具有与竖直上升两相流不同的相界面结构特征及输运特性。本文对竖直下降管内的气水两相流进行了实验研究,运用微型四头电导探针对7.5、31.5及55.5倍管径横截面处的空泡份额、相界面浓度、气泡直径、气泡频率及气泡速度等相界面结构参数的局部分布进行了测量。分析获得了相界面结构参数的沿程变化规律,并研究了气相表观流速对相界面结构发展的影响及一维相界面结构输运特性。发现竖直下降泡状流的升力指向管中心,导致相界面结构参数基本呈中心峰值分布;气相表观流速的增大会提高空泡份额和相界面浓度分布的峰度;竖直下降两相流在距入口31.5倍管径处基本达到充分发展。

关键词: 竖直下降, 两相流, 电导探针, 相界面结构, 输运特性

Abstract:

The vertical-downward two-phase flow has different interfacial structures and transport characteristics compared with vertical-upward two-phase flow. The air-water two-phase flow in vertical-downward pipes was investigated in the paper. The four-sensor conductivity probe was used to measure the distribution of local two-phase flow parameters (void fraction, interfacial area concentration, bubble diameter, bubble frequency, and bubble velocity) across pipe cross-sections at 7.5, 31.5 and 55.5 times pipe diameters. The experimental data were used to analyze the development characteristics of two-phase flow parameters across the pipe cross-section and along the flow direction, the effect of gas-phase superficial velocity, and the one-dimensional transport of the averaged two-phase flow parameters. The results show that the lift force points toward the pipe center, which results in a center-peaked void fraction distribution in vertical-downward two-phase flow. The kurtosis of the void fraction profile and the interfacial area concentration profile increase with the gas-phase superficial velocity. The vertical-downward two-phase flow becomes nearly fully developed at 31.5 times pipe diameters.

Key words: vertical-downward, two-phase flow, conductivity probe, interfacial structure, transport characteristic