TY - JOUR
T1 - Effect of upstream wake on flow characteristics of tip leakage at squealer tip with large-scale depth
AU - Bi, Shuai
AU - Han, Xingsi
AU - Wu, Ao
AU - Zhou, Jie
AU - Zhao, Majie
N1 - Publisher Copyright:
© 2026 Elsevier Masson SAS.
PY - 2026/8
Y1 - 2026/8
N2 - The squealer tip is a common configuration used to enhance the aerothermal performance of the turbine. However, in the complex working environment of an aircraft engine, the scale influence of cavity depth interacts with rotational factor of the blade, and simultaneously superimposes the periodic sweeping formed by the upstream wake, causing complicated coupling characteristics of the flow in the cascade channel and tip clearance. This paper concentrates on the goal of suppressing clearance leakage. Regarding the squealer tip, it conducts a study on the transient aerodynamic features of leakage flow. Firstly, clarify the mechanism of the influence of cavity scales on leakage flow; next, for the cavity with large-scale depth, consider the effect of upstream wake on the flow inside the clearance, illustrate mechanism of upstream wake's effect on vortex system and mixing loss of clearance leakage, and analyze transient characteristics of leakage flow under the influence of upstream wake. In the study, it was found that the transport effect can effectively reduce the flow direction vorticity of leakage vortex. Under influence of the upstream wake, the relative leakage and flow loss decreased by 18.22% and 3.97%, respectively. The periodic sweeping of the upstream wake causes periodic fluctuations in the leakage amount and entropy increase loss.
AB - The squealer tip is a common configuration used to enhance the aerothermal performance of the turbine. However, in the complex working environment of an aircraft engine, the scale influence of cavity depth interacts with rotational factor of the blade, and simultaneously superimposes the periodic sweeping formed by the upstream wake, causing complicated coupling characteristics of the flow in the cascade channel and tip clearance. This paper concentrates on the goal of suppressing clearance leakage. Regarding the squealer tip, it conducts a study on the transient aerodynamic features of leakage flow. Firstly, clarify the mechanism of the influence of cavity scales on leakage flow; next, for the cavity with large-scale depth, consider the effect of upstream wake on the flow inside the clearance, illustrate mechanism of upstream wake's effect on vortex system and mixing loss of clearance leakage, and analyze transient characteristics of leakage flow under the influence of upstream wake. In the study, it was found that the transport effect can effectively reduce the flow direction vorticity of leakage vortex. Under influence of the upstream wake, the relative leakage and flow loss decreased by 18.22% and 3.97%, respectively. The periodic sweeping of the upstream wake causes periodic fluctuations in the leakage amount and entropy increase loss.
KW - Clearance flow
KW - Depth of cavity
KW - Squealer tip
KW - Transient characteristics
KW - Upstream wake
UR - https://www.scopus.com/pages/publications/105031145677
U2 - 10.1016/j.ast.2026.111949
DO - 10.1016/j.ast.2026.111949
M3 - Article
AN - SCOPUS:105031145677
SN - 1270-9638
VL - 175
JO - Aerospace Science and Technology
JF - Aerospace Science and Technology
M1 - 111949
ER -