超临界二氧化碳离心压缩机设计及性能预测  

Design and performance prediction of supercritical carbon dioxide centrifugal compressor

作　　者：孙恩慧[1,2] 杨振宇[1,2] 廖凯龙 张磊[1,2] 安光耀 李永毅[1,2] SUN Enhui;YANG Zhenyu;LIAO Kailong;ZHANG Lei;AN Guangyao;LI Yongyi(Department of Power Engineering,North China Electric Power University,Baoding 071003,China;Hebei Key Laboratory of Low Carbon and High Efficiency Power Generation Technology,North China Electric Power University,Baoding 071003,China)

机构地区：[1]华北电力大学动力工程系,河北化保定071003 [2]华北电力大学河北省低碳高效发电技术重点实验室,河北保定071003

出　　处：《热力发电》2023年第6期127-134,156,共9页Thermal Power Generation

基　　金：国家自然科学基金面上基金项目(52076079);国家自然科学基金青年基金项目(52206010)。

摘　　要：离心压缩机是超临界二氧化碳(S-CO_(2))循环系统中的关键部件之一,对系统的效率和稳定运行起决定性作用。区别于传统空气工质压缩机,S-CO_(2)工质的独特物性使得压缩机内部流场更为复杂;基于空气物性特点建立的损失模型也需要做针对性的修正以满足S-CO_(2)离心压缩机的性能预测要求,因此需要数值模拟研究探明压缩机内部流场特性,以此对压缩机性能预测方法做相应的改进。首先开展压缩机一维气动参数设计,并在一维设计参数的基础上建立三维模型,分析压缩机内部流场特点,发现分流叶片对内部流场有较大影响,同时变工况下叶轮内部流场发生改变也会引起出口气流角的变化,基于此,对压缩机非设计工况下滑移因子和计算叶片数进行修正,同时改进表面摩擦系数以预测压缩机的非设计工况性能。数值模拟结果表明,改进后模型的预测误差显著降低,非设计工况下平均效率误差从2.03%下降到0.16%。Centrifugal compressor is one of the key components in supercritical carbon dioxide(S-CO_(2))cycle system,which plays a decisive role in the efficiency and stable operation of the system.Different from the traditional air compressor,the unique physical properties of S-CO_(2) working medium make the internal flow field of the compressor more complex.The loss model established based on the physical characteristics of air also needs to be modified specifically to meet the performance prediction requirements of S-CO_(2) centrifugal compressor.Therefore,numerical simulation is needed to investigate the internal flow field characteristics of the compressor,so as to improve the compressor performance prediction method accordingly.Firstly,one-dimensional aerodynamic parameters of the compressor were designed,and a three-dimensional model was established based on the onedimensional design parameters to analyze the characteristics of the internal flow field of the compressor.It was found that the shunt blade had a great influence on the internal flow field,and changes in the internal flow field of the impeller under varying working conditions would also cause changes in the outlet flow Angle.Based on this,The sliding factor and the calculated blade number of the compressor under off-design conditions were corrected,and the surface friction coefficient was improved to predict the performance of the compressor under off-design conditions.The numerical simulation results show that the prediction error of the improved model is significantly reduced,and the average efficiency error decreases from 2.03%to 0.16%under off-design conditions.

关 键 词：超临界二氧化碳 离心压缩机 一维设计 数值模拟 性能预测 滑移因子 

分 类 号：TH452[机械工程—机械制造及自动化]