半开式和闭式超临界二氧化碳离心叶轮关键参数
Key Parameters of Semi-Open and Enclosed Supercritical Carbon Dioxide Centrifugal Impellers
赵峰 1张旭阳 1杜晓东1
作者信息
- 1. 上海船舶设备研究所,上海 200031
- 折叠
摘要
基于某型超临界二氧化碳离心压缩机的工作条件,开展半开式和闭式等 2种型式离心叶轮关键结构参数研究,对比这 2 种型式叶轮的气动性能,开展三维数值仿真和流场分析.结果表明:叶顶前缘与尾缘间隙为0.65 mm、叶片后弯角为 30°、叶片数为6 时,半开式离心叶轮的总静效率最高达64.918 6%;叶片后弯角给定48°、叶顶密封间隙为0.25 mm、叶片数为15 时,闭式离心叶轮的总静效率最高达74.808 6%;在保证压比满足要求的前提下,闭式离心叶轮的一维总静效率高于半开式离心叶轮的一维总静效率11.132 2%以上,三维总对总等熵效率高于半开式离心叶轮的三维总对总等熵效率16.766 0%;半开式离心叶轮出口处的压力变化较剧烈,熵增区域较大,无叶扩压器顶部存在涡流,流动损失较大;闭式离心叶轮出口处存在压力梯度,熵增范围较小,无叶扩压器速度分布较均匀,流动损失较小.
Abstract
Based on the working conditions of a certain type of supercritical carbon dioxide centrifugal compressor,the key structural parameters of two types of centrifugal impellers,semi-open and enclosed,are studied.The aerodynamic performance of these two types of impellers is compared,and the three-dimensional numerical simulation and the flow field analysis are carried out.The results show that when the clearance between the leading and trailing edges of the blade tip is 0.65 mm,the blade back bending angle is 30°,and the number of blades is 6,the total static efficiency of the semi-open centrifugal impeller is as high as 64.918 6%;The total static efficiency of the enclosed centrifugal impeller can reach up to 74.808 6%when the blade back bending angle is given at 48°,the blade tip sealing clearance is 0.25 mm,and the number of blades is 15;On the premise of ensuring that the pressure ratio meets the requirements,the one-dimensional total static efficiency of a enclosed centrifugal impeller is higher than that of a semi-open centrifugal impeller by more than 11.132 2%,and the three-dimensional total isentropic efficiency is higher than that of a semi-open centrifugal impeller by 16.766 0%.The pressure at the outlet of the semi-open centrifugal impeller changes violently,the entropy increase area is large,and there is eddy current at the top of the vaneless diffuser,which leads to large flow losses;There is a pressure gradient at the outlet of the enclosed centrifugal impeller,the entropy increase range is relatively small,and the velocity distribution of the vaneless diffuser is relatively uniform,which leads to relatively small flow losses.
关键词
超临界二氧化碳/半开式/闭式/离心叶轮/关键参数Key words
supercritical carbon dioxide/semi-open/enclosed/centrifugal impeller/key parameter引用本文复制引用
出版年
2025
NETL
NSTL
万方数据