盘腔封严流对主流影响的瞬态POD分析  

Transient POD Analysis of Influence of Cavity Seal Purge Flow on Mainstream

作　　者：刘春辉 陈二云[1] 杨爱玲[1] LIU Chun-hui;CHEN Er-yun;YANG Ai-ling(School of Energy and Power Engineering,University of Shanghai for Science and Technology,Shanghai,China,Post Code:200093)

机构地区：[1]上海理工大学能源与动力工程学院,上海200093

出　　处：《热能动力工程》2023年第3期51-58,共8页Journal of Engineering for Thermal Energy and Power

基　　金：国家自然科学基金(51106099)。

摘　　要：盘腔封严冷气泄漏流与主流的相互干涉对燃气轮机效率有重要影响。基于带有叶片的转静系盘腔模型的瞬态数值解,采用本征正交分解(POD)方法对主流场进行分解,分析瞬态流场的湍流能量、模态系数与湍流结构,研究封严泄漏流与主流场的干涉以及轴向封严间隙与径向封严间隙对泄漏流的影响。结果表明:在不同相对叶高处湍流能量占比存在差异,在相对叶高50%处,径向封严比轴向封严湍流能量高19.74%,相对差值达到最大;在相对叶高30%处,径向封严比轴向封严湍流能量高15.93%,绝对差值达到最大;主要湍流结构和次要湍流结构在模态系数频域特性、模态湍流结构上表现出差异,径向封严对盘腔流体与主流流体交互作用的阻碍强化了封严间隙对主流的干扰。The interference between cavity seal purge flow and mainstream has an important effect on gas turbine efficiency.In this paper,based on the transient numerical solution of the rotor disk cavity model with blades,the main flow field is decomposed by using proper orthogonal decomposition(POD) method,the turbulent energy,modal coefficient and turbulent structure of the transient flow field is analyzed,the interference between the sealing leakage flow and the main flow field as well as the influence of the axial and radial sealing clearances on the leakage flow are studied.The results show that the proportions of turbulent energy at different relative blade heights are different.The turbulence energy of radial seal is 19.74% higher than that of axial seal at 50% relative blade height,the relative difference reaches the maximum;and the turbulence energy of radial seal is 15.93%higher than that of axial seal at 30% relative blade height,the absolute difference reaches the maximum;the main turbulent structure and the minor turbulent structure are different in modal coefficient frequency domain characteristic and modal turbulent structure.The obstruction of radial seal on the interaction between the fluid in the disc cavity and the mainstream fluid strengthens the interference of seal clearance on the mainsream.

关 键 词：盘腔封严 数值模拟 本征正交分解 湍流 

分 类 号：TK472[动力工程及工程热物理—动力机械及工程]