摘要
透平膨胀机是二氧化碳储能系统的关键装备,透平叶轮的结构参数优化有利于更好地提高透平膨胀机的整体性能。本文以某百千瓦级二氧化碳储能系统向心透平为研究对象,首先通过气动设计得到该二氧化碳透平的主要结构参数,然后基于Numeca开展流场仿真,分析了叶轮叶片数、叶轮入口角和叶轮出口角对流动特性的影响规律,进一步研究了叶顶间隙内的泄漏流和损失,最后探究了非定常流动特性下透平性能的变化规律。结果表明:随着叶轮叶片数的增加,叶轮流道中的低马赫数区域占比先降低后增加;叶轮入口角和叶轮出口角显著影响透平内流动分离区域和涡面积分布,优化叶轮角后的透平等熵效率达83.65%,较初始设计提高了0.75%;透平等熵效率随叶顶间隙的增加而减小,且近似呈线性变化;喷嘴尾迹流会引起叶轮内的非定常流动,且透平等熵效率较定常工况时下降了0.57%。
The turbine expander is a key component in a carbon dioxide(CO_(2))energy storage system.Optimizing the structural parameters of the turbine impeller improves overall expander performance.This study investigates a centripetal turbine in a hundred-kilowattclass CO_(2) energy storage system.Initially,the main structural parameters of the CO_(2) turbine are defined through aerodynamic design.A subsequent flow field simulation using Numeca software evaluates the effects of impeller blade number,inlet angle,and outlet angle on flow characteristics.In addition,leakage flow and losses in the impeller top clearance are examined.Finally,turbine performance under unsteady flow conditions is assessed.The results demonstrate that increasing the impeller blade number causes the percentage of the low Mach number region in the impeller channel to decrease and then increase.Both the impeller inlet and outlet angles significantly affect the flow separation region and vortex distribution.After optimization,the turbine's isentropic efficiency reaches 83.65%,an increase of 0.75% relative to the initial design.Furthermore,the isentropic efficiency decreases approximately linearly with greater impeller top clearance,and nozzle wake flow induces unsteady conditions,reducing efficiency by 0.57%compared to steady flow.
作者
沈代兵
郝佳豪
宋衍昌
杨俊玲
张振涛
越云凯
SHEN Daibing;HAO Jiahao;SONG Yanchang;YANG Junling;ZHANG Zhentao;YUE Yunkai(State Key Laboratory of Cryogenic Science and Technology,Technical Institute of Physical and Chemistry,Chinese Academy of Sciences,Beijing 100190,China;University of Chinese Academy of Sciences,Beijing 100049,China;Changsha Borui Energy Technology Co.,Ltd.,Changsha 410205,Hunan,China;Research Institute of Energy Storage Industrial Technology of Hebei Province,Shijiazhuang 050051,Hebei,China)
出处
《储能科学与技术》
北大核心
2025年第3期1270-1285,共16页
Energy Storage Science and Technology
基金
国家自然科学基金(52206032)
中国科学院稳定支持基础研究领域青年团队计划(YSBR-043)。
关键词
二氧化碳储能
透平膨胀机
结构参数
叶顶间隙泄漏
非定常流动
carbon dioxide energy storage
turbine expander
structural parameter
impeller top clearance leakage
unsteady flow
作者简介
第一作者:沈代兵(2000-),男,硕士研究生,研究方向为二氧化碳储能系统透平膨胀机,E-mail:shendaibing22@mails.ucas.ac.cn;通信作者:越云凯,高级工程师,研究方向为二氧化碳储能系统,E-mail:yueyunkai@mail.ipc.ac.cn。
