圆形截面凝汽器布管设计及换热性能分析  

Tube Layout Design and Heat Transfer Performance Analysis of Circular Cross-section Condenser

作　　者：秦启君 周旭 陈令章 QIN Qijun;ZHOU Xu;CHEN Lingzhang(Clean Combustion and Flue Gas Purification Key Laboratory of Sichuan,Chengdu 611731,China;Dongfang Electric Group Dongfang Boiler Co.,Ltd.,Zigong 643001,China)

机构地区：[1]清洁燃烧与烟气净化四川省重点实验室,四川成都611731 [2]东方电气集团东方锅炉股份有限公司,四川自贡643001

出　　处：《山东电力技术》2024年第5期56-62,共7页Shandong Electric Power

基　　金：国家重点研发计划青年科学家项目(2022YFB4100500)。

摘　　要：凝汽器是蒸汽动力系统重要的设备之一,其换热性能直接影响整个系统的运行效率。多领域对更高效凝汽器的需求不断涌现,针对凝汽器的结构设计迭代与换热性能优化的研究具有重要意义。文中在FLUENT计算平台中,基于多孔介质模型通过自定义函数嵌入管间换热模型、质量汇与阻力模型,分析了一种圆形截面凝汽器布管方式的换热性能。结果表明,相比于管内冷却水工况的变化,蒸汽流速变化引起的管外热阻变化更大程度地影响平均换热系数。依据实际运行工况参数范围,入口蒸汽流速为30~70 m/s,冷却水流速为0.72~2.15 m/s,冷却水温度为25~28℃,平均换热系数最大可达3562 W(/m^(2)·K),同时压降范围为211~525 kPa。该结构设计表现出较好的换热性能和较低的压力损失,但局部不凝结气体的积聚表明该结构仍有进一步改进的空间。The vapor condenser is one of the important equipment in the steam power generation system,and its heat exchange performance directly affects the operational efficiency of the entire system.The demand for more efficient condensers in multiple fields is constantly emerging,and the research on the innovative structural design and the optimization of heat transfer performance of condensers is of great significance.The heat transfer model,distributed mass sink and resistance model were compiled into the FLUENT software equipped with porous medium model through user defined functions.The heat transfer performance of a new type of circular cross-section condenser tube layout was analyzed.The results showed that,compared to the change of cooling water conditions inside the tube,the change of thermal resistance outside referring to steam flow rate has a greater impact on the overall average heat transfer coefficient.According to the actual operating condition parameter range,the inlet vapor flow rate is 30~70 m/s,the cooling water flow rate is 0.72~2.15 m/s,the cooling water temperature is 25~28℃,the maximum average heat transfer coefficient is up to 3562 W(/m^(2)·K),and the pressure drop range is 211~525 kPa.The structural design exhibits higher heat transfer performance and lower pressure drop,while the accumulation of local non-condensable gas indicates that there is still room for further improvement in the structure design.

关 键 词：凝汽器 管束布置 数值模拟 多孔介质 

分 类 号：TK172[动力工程及工程热物理—热能工程]