影响因子：5.6

所属单位：南京航空航天大学

发表刊物：Aerospace Science and Technology

项目来源：National Science and Technology Major Project (2017-III-0010-0036).

关键字：Over-tip leakage flow Transonic flow VLES method Tip gap variation Loss mechanism

摘要：Transonic turbine blade Over-Tip Leakage (OTL) flow has significant effects on turbine efficiency and blade thermal load. At present, most of the numerical studies on OTL flow are based on Reynolds-Averaged Navier-Stokes (RANS) method. However, it is difficult to characterize the physical mechanisms of transonic OTL flow accurately due to the inherent shortcomings of RANS method, especially for the unsteady characteristics. To understand the underlying loss mechanisms and aerothermal characteristics of the transonic OTL flow with tip gap variations, the present study applies a Very Large Eddy Simulation (VLES) method based on Wilcox k–ωmodel to study a transonic cascade OTL flow. The feasibility and accuracy of the VLES turbulence model in OTL flow simulations are confirmed by numerical assessments comparison with the experimental results. The detailed flow structure and its effect on the losses of tip leakage flow are studied for different cases with varying tip gap heights. It is observed that the flow structures including separation vortex and shock waves in the gap become more complex with increasing the tip gap. The mass flow rate, pressure loss, entropy generation, and aerothermal performance for different tip gap heights are further discussed.

论文类型：期刊论文

是否译文：否

发表时间：2021-01-27

收录刊物：SCI

合写作者：韩省思

第一作者：王天壹

通讯作者：宣益民