文章摘要
李琪飞,张建勋,刘萌萌,刘谦.水泵水轮机泵工况下内部空化特性分析[J].热能动力工程,2017,32(10):84-89
水泵水轮机泵工况下内部空化特性分析
Analysis of the Internal Cavitation Characteristics of a Reversible Turbine under the Pump Condition
  
DOI:
中文关键词: 水泵水轮机  泵工况  空化流动  空泡体积分数  数值模拟
英文关键词: reversible turbine, pump condition, cavitation flow, void fraction
基金项目:国家自然科学基金项目(51566009)
作者单位
李琪飞 兰州理工大学 能源与动力工程学院 
张建勋 兰州理工大学 能源与动力工程学院 
刘萌萌 兰州理工大学 能源与动力工程学院 
刘谦 兰州理工大学 能源与动力工程学院 
摘要点击次数: 583
全文下载次数: 0
中文摘要:
      为研究空化条件下水泵水轮机泵工况的内部空化特性,基于ANSYS CFX 软件应用 k-ε湍流模型、均质多相模型和Rayleigh-Plesset方程,对某抽水蓄能电站模型机进行了全流道非定常空化流动数值计算。根据模拟结果预测了水泵水轮机泵工况工作无空化时的能量特性和空化发生时的空化性能,并与试验数据对比。结果表明:流场数值计算成功地捕获到了空化发生、发展及空间演变过程;随着空化系数的变化,空泡在叶片背面进口附近产生,然后沿着流线向叶轮出口扩散,并随着流道过流面积的增大向叶片工作面扩展,直接影响叶片上的压力分布和叶片中间流线上叶片载荷分布;在空化严重时,会造成叶轮流道内流动紊乱的严重堵塞,导致效率的大幅下降,对机组安全稳定运行非常不利。
英文摘要:
      To investigate the internal cavitation characteristics of a reversible turbine operating under the pump conditions in the presence of cavitation, on the basis of the software ANSYS CFX, the k-ε turbulent flow model, homogeneous multiphase model and Rayleigh-Plesset equation were used to perform a non-steady cavitation flow numerical calculation of the flow in the whole flow passages of the model machine in a pumped storage power plant. According to the simulation results, the energy characteristics of the reversible turbine operating under the pump conditions in the absence of cavitation and its cavitation performance in the presence of cavitation were predicted and a comparison was made with the test data. It has been found that the numerical calculation of the flow fields can successfully capture the occurrence, development and spatial evolution process of the cavitation. As the cavitation coefficient changes, the air bubbles will occur at places close to the leading edge of blades on the back surface, then diffuse themselves all their way to the outlet of the impeller along the streamlines and extend themselves to the working surface of the blades with an increase of the flowing-through area of the flow passage, thus directly influencing the pressure distribution and the load distribution on the blades along the streamlines between the blades. When the cavitation becomes worsened, the disorder in the flow and serious blockage in the flow passages of the impeller may result, therefore leading to a decrease of the efficiency by a great margin and very unfavorable for a safe and reliable operation of the unit.
查看全文   查看/发表评论  下载PDF阅读器
关闭