PDF《超超临界 1 000 MW 二次再热机组锅炉》

第46 卷第8期热力发电Vol.

46 No.8

2017 年8月THERMAL POWER GENERATION Aug.

2017 收稿日期:2017-04-13 基金项目:国家重点研发计划项目(2016YFB0600201) Supported by:National Key Research and Development Program (2016YFB0600201) 第一作者简介:茆凯源(1992―),男,硕士研究生,主要研究方向为多相流动与传热,[email protected]. 通讯作者简介:杨冬(1967―),男,教授,博士生导师,主要研究方向为多相流动与传热,[email protected]. 超超临界

1 000 MW 二次再热机组锅炉 水动力及流动不稳定性计算分析 茆凯源

1 ,聂鑫1,谢海燕

1 ,杨冬1,王凤君

2 ,黄莺2(1.西安交通大学动力工程多相流国家重点实验室,陕西 西安 710049;

2.哈尔滨锅炉厂有限责任公司高效清洁燃煤电站锅炉国家重点实验室,黑龙江 哈尔滨 150046) [摘要]大唐雷州电厂超超临界

1 000 MW 二次再热机组锅炉为 Π 型布置.由于 Π 型锅炉汽水流程 复杂,可能会存在流量分配不均的风险,导致水冷壁超温造成事故.在宽负荷运行和快速 变负荷调峰过程中,由于给煤量的扰动,水冷壁易出现流动不稳定现象.本文采用流动网 络系统方法计算了锅炉在 BMCR 负荷时的质量流速分配、 工质汽温以及金属温度分布, 并对30%THA 负荷进行了流动不稳定性校核, 并在此基础上, 分析了水冷壁的优化设计及安 全运行特性.计算结果表明,水冷壁能避免管间应力过大和拉裂,在施加热负荷扰动后流 量均能恢复稳定,锅炉水冷壁运行是安全可靠的. [关键词]超超临界;

锅炉;

二次再热;

水冷壁;

水动力特性;

流动不稳定性;

流动网络系统 [中图分类号]TK124 [文献标识码]A [文章编号]1002-3364(2017)08-0036-06 [DOI 编号]10.3969/j.issn.1002-3364.2017.08.036 Computational analysis on hydrodynamic characteristics and flow instability of an ultra supercritical

1 000 MW double-reheat unit boiler MAO Kaiyuan1 , NIE Xin1 , XIE Haiyan1 , YANG Dong1 , WANG Fengjun2 , HUANG Ying2 (1. State Key Laboratory of Multiphase Flow in Power Engineering, Xi'

an Jiaotong University, Xi'

an 710049, China;

2. State Key Laboratory of Efficient and Clean Coal-fired Utility Boilers, Harbin Boiler Company Limited, Harbin 150046, China) Abstract: The ultra supercritical

1 000 MW unit boiler with double-reheat cycle in Datang Leizhou Power Plant adopts Π type arrangement. Due to the complexity of water flow in Π type boiler, there exists the risk of uneven distribution of mass flow rate, which may result in the water wall overheat accident. In the processes of unit wide load operation and fast peak shaving, flow instability may occur in the water wall of the boiler due to the coal supply disturbance. To solve these problems, the distributions of mass flow rate, working fluid and metal temperatures in water wall at BMCR load were calculated by flow network system method, and the flow instability was checked for 30%THA load. On this basis, the optimal design and safe operation of the water wall were analyzed. The calculation results show that the water wall can avoid excessive stress between pipes and tension crack. The mass flow rate can finally restore stability after being disturbed by heat load. The water wall is safe and reliable. Key words: ultra supercritical, boiler, double reheat, water wall, hydrodynamic characteristics, flow instability, flow network system 大唐雷州电厂采用超超临界

1 000 MW 二次再 热燃煤机组.与一次再热相比,二次再热能够有效 提高机组热效率、减少污染物排放[1] .同时二次再 热机组锅炉水冷壁入口流量变小,水温升高,使得 BMCR 负荷时金属壁温较高,这对水冷壁材料的选 择提出更高的要求.因此需要有准确地计算和分析 来保证水冷壁的安全运行. 另外, 为满足调峰要求, 机组一般采用变压运行方式来实现快速变负荷,由第8期茆凯源 等 超超临界