摘要
在考虑密封泄漏损失的情况下,对小流量二氧化碳离心叶轮进行了三维黏性计算流体动力学分析,对比了考虑密封泄漏前后的计算结果.在设计工况下,叶轮等熵效率下降了8.1%,表明对小流量离心压缩机性能及主流流动结构进行准确的数值预测,必须考虑密封泄漏.为了揭示密封泄漏对离心叶轮性能的影响,通过改变迷宫密封的间隙得到了不同的密封结构,并在设计工况、小流量工况和大流量工况下分别进行了数值分析.结果表明,在一定流量工况下,随着密封间隙的增大,密封泄漏损失系数近似线性增大,离心叶轮等熵效率随之近似线性地下降.
The analysis with the three-dimensional viscous computational fluid dynamics （CFD） was carried out for a carbon dioxide centrifugal impeller with a low flow coefficient. The results show that the impeller isentropic efficiency decreases by 8. 1 percent at the design mass flow rate with the consideration of the seal leakage compared with that without the consideration of the seal leakage. It is suggested that the seal leakage should be considered in the numerical simulation to predict accurately the performance and the flow in impellers with a low flow coefficient. In order to explore the effect of the seal leakage on the performance of the impeller, the seal clearance was changed and the numerical simulation was performed on the centrifugal impeller with different seal configurations at the low and high mass flow rates as well as the design mass flow rate, respectively. Our results indicate that, at a given mass flow rate, the seal leakage loss coefficient increases and the impeller isentropic efficiency decreases almost linearly with the increase in the seal clearance.
出处
《西安交通大学学报》
EI
CAS
CSCD
北大核心
2010年第11期23-27,共5页
Journal of Xi'an Jiaotong University
基金
国家自然科学基金资助项目(50725621)
关键词
离心叶轮
小流量系数
密封泄漏
centrifugal impeller
low flow coeffieient
seal leakage
