自然科学版 英文版
自然科学版 英文版
自然科学版 英文版

您目前所在的位置:首页 - 期刊简介 - 详细页面

中南大学学报(自然科学版)

Journal of Central South University

第48卷    第11期    总第279期    2017年11月

[PDF全文下载]    [Flash在线阅读]

    

文章编号:1672-7207(2017)11-3108-08
直接空冷凝汽器干式吹扫系统的喷嘴流场特性
何青1,张暕1,杜冬梅1,刘婧1,赵晓彤2

(1. 华北电力大学 能源动力与机械工程学院,北京,102206; 2. 中国电力科学研究院系统所,北京,102902)

摘 要: 针对干式吹扫系统压缩空气从喷嘴射入到凝汽器翅片时,其速度减小影响吹扫效果的问题,运用射流动力学和计算流体力学理论对喷嘴外流场进行模拟,分析喷嘴结构和喷嘴到翅片的距离(靶距)对喷嘴射流能力的影响。研究结果表明:在相同靶距和工作压力下,与圆柱长度30 mm、直径为1.6 mm的喷嘴相比,圆柱长度为25 mm、直径为1.8 mm的喷嘴射程更长,速度更高,射流能力更强;在相同条件下,与单孔喷嘴相比,双孔喷嘴的射程更长,射流面积更大,喷嘴射流能力更强。靶距越大,翅片入口的空气速度越小,射流面积则先增大后减小;为满足较高的吹扫效果,当喷嘴入口压力为0.65 MPa时,选取收缩角为40°,圆柱长度为25 mm,圆柱直径为1.8 mm的喷嘴结构,采用双孔布置,最佳靶距为40 mm。

 

关键字: 直接空冷系统;凝汽器;干式吹扫系统;喷嘴;流场特性

Characteristics of nozzle outflow field of dry air blowing system for direct air-cooled condenser
HE Qing1, ZHANG Jian1, DU Dongmei1, LIU Jing1, ZHAO Xiaotong2

1. School of Energy Power and Mechanical Engineering, North China Electric Power University, Beijing 102206, China; 2. Division of Electric Power System, China Electric Power Research Institute, Beijing 100192, China

Abstract:Considering that when compressed air injects into the condenser fin from nozzle, its speed is weakened, which influences the effect of air blowing, the outflow field of nozzle was simulated by jet dynamics and computational fluid dynamics. The influences of the structure and distance from the nozzle to the fin (target distance) on jet ability were analyzed. The results show that when the target distance and work pressure are the same, the nozzle whose cylinder length is 25 mm and cylinder diameter is 1.8 mm has a longer range, a higher speed and better jet ability than the one whose cylinder length is 30 mm and cylinder diameter is 1.6 mm. Compared with the single hole nozzle, the double hole nozzle has a longer range, a larger area and better jet ability under the same conditions. With the increase of the target distance, the air velocity at the fin entrance decreases, and the jet area increases firstly and then decreases. In order to achieve better blowing effect, the nozzle which has a contraction angel of 40°, a cylinder length of 25 mm, and a cylinder diameter of 1.8 mm is selected and double holes layout is adopted, and the best target distance of the nozzle is 40 mm when the inlet absolute pressure of the nozzle is 0.65 MPa.

 

Key words: direct air-cooled system; condenser; dry air blowing system; nozzle; flow field characteristics

中南大学学报(自然科学版)
  ISSN 1672-7207
CN 43-1426/N
ZDXZAC
中南大学学报(英文版)
  ISSN 2095-2899
CN 43-1516/TB
JCSTFT
版权所有:《中南大学学报(自然科学版、英文版)》编辑部
地 址:湖南省长沙市中南大学 邮编: 410083
电 话: 0731-88879765(中) 88836963(英) 传真: 0731-88877727
电子邮箱:zngdxb@csu.edu.cn 湘ICP备09001153号