水电机组导轴承冷却器含杂质水流流动特性及结构优化

Flow Characteristics of Impurity-Laden Water and Structural Optimization of Guide Bearing Cooler for Hydraulic Generating Units

中文关键词:水导轴承  冷却器  螺旋扁管  数值模拟  结构优化

keywords:guide bearing  cooler  spiral flat tube  numerical simulation  structural optimization

中文摘要:针对水冷式冷却器冷却水中杂质易在圆管中发生沉降、堆积与附着形成垢面、严重影响冷却器的换热性能问题，通过对冷却器的强化传热分析，提出将圆管优化为螺旋扁管，并开展了半环式冷却器模拟实际运行工况的数值分析。对流速、压力、杂质以及温度分布的分析结果表明：优化后的螺旋扁管式冷却器可形成良好的湍流组织，能有效提升防堵塞能力；水流紊乱度、流速的增加能有效提高冷却器的换热效率。研究结果对水轮发电机组导轴承冷却器的设计、生产和运行有一定指导意义。

Abstract:In water-cooled coolers，impurities in cooling water tend to settle，accumulate and adhere to the inner wall of round tubes，forming fouling layers and seriously degrading the heat transfer performance.Aiming at this problem，this paper optimizes conventional round tubes into spiral flat tubes based on enhanced heat transfer analysis，and conducts numerical simulation on semi-annular coolers under actual operating conditions.The analysis on flow velocity，pressure，impurity distribution and temperature distribution shows that the spiral flat tube can generate strong turbulent flow and effectively improve the anti-clogging performance.Higher flow turbulence and flow velocity can further enhance the heat transfer efficiency of the cooler.The research results provide references for the design，manufacture and operation of guide bearing coolers for hydraulic generating units.