摘要
超临界二氧化碳透平被广泛用于太阳能发电系统中,但局部损失导致该透平流动中部分区域工质处于亚临界区。为了探究二氧化碳在跨临界区物性对透平的影响,进行了喷管实验和单级轴流透平的热力气动设计、三维造型及数值模拟。结果表明:二氧化碳物性在跨临界区急剧变化,易产生流动分离和回流等现象;设计透平在各工况下喷嘴尾缘、动叶吸力面前缘等局部压降区域易出现跨临界现象,并伴随有透平效率不同程度降低;增大出口压力、升高温度、调整转速或优化翼型,均可避免跨临界情况发生,从而提高透平效率。
The supercritical carbon dioxide(S-CO2)turbine has been widely used in solar power generation systems,but local loss may cause partial working medium to flow in the subcritical region of the turbine.To explore the influence of physical property changes of carbon dioxide in the transcritical region on the performance of the turbine,nozzle experiments,thermodynamic and aerodynamic design,three-dimensional modeling and numerical simulation were conducted for a single-stage axial-flow turbine.It has been found that the physical properties of carbon dioxide change rapidly in the transcritical region,which is easy to produce flow separation,reflux and other phenomena.The transcritical region tends to appear at the trailing edge of nozzles and at the leading edge on suction surface of moving blades,where the efficiency drops to some extent.The appearance of transcritical region could be avoided by increasing the outlet pressure,elevating the temperature,and adjusting the speed or optimizing the airfoil,etc.,thus to improve the efficiency of the turbine.
作者
王智
匡轩毅
刘亚丽
李志彬
闫锐鸣
WANG Zhi;KUANG Xuanyi;LIU Yali;LI Zhibin;YAN Ruiming(MOE's Key Lab of Condition Monitoring and Control for Power Plant Equipment,North China Electric Power University,Baoding 071003,Hebei Province,China)
出处
《动力工程学报》
CAS
CSCD
北大核心
2020年第6期509-516,共8页
Journal of Chinese Society of Power Engineering
基金
国家自然科学基金资助项目(51306059)。
关键词
跨临界物性
超临界二氧化碳
轴流透平
数值模拟
physical property in transcritical region
supercritical carbon dioxide
axial turbine
numerical simulation
