Session: 15-07: Numerical Studies of Internal Cooling

Submission Number: 177642

Unsteady Flow and Heat Transfer Mechanisms of Dual-Jet Impingement Drainage Cooling Under Film Extraction by Large Eddy Simulation 

Impingement cooling serves as an efficient thermal management technique for turbine components, however conventional configurations are often compromised by adverse crossflow effects. Impingement drainage cooling (IDC) offers an advanced jet impingement strategy with a modular architecture comprising separated cooling chambers and drainage channels. This design enables efficient extraction of spent coolant through dedicated drainage channels, mitigating its interference with impinging jets and promoting potential coolant reuse. IDC configurations are categorized into single-jet and multi-jet types based on the number of jets per cooling unit. To further improve turbine blade protection, external film cooling is generally incorporated. This study employs large eddy simulation (LES) to examine the internal heat transfer behavior of a dual-jet IDC system under film extraction, with particular emphasis on the underlying interaction and coupling mechanisms between film extraction and impinging jets. Multiple film hole configurations varying in diameter and placement are investigated. A statistical convergence analysis of unsteady simulations is performed, and the fundamental flow dynamics within the film-cooled IDC structure are elucidated. Space-only proper orthogonal decomposition (POD) is applied to evaluate how film extraction influences jet interactions. Results reveal that cooling jet interactions within the confined space generate large-scale coherent structures, whose intensity is notably attenuated by film extraction. Additionally, a probabilistic collocation method (PCM) is used to quantify the sensitivity of heat transfer characteristics on the leading-edge target surface to film hole diameter. Findings indicate that areas of high heat transfer—especially near the impingement stagnation point and the wall-jet collision zone—exhibit significant sensitivity to film suction. The wall-jet collision zone shows particularly strong sensitivity due to the direct presence of film holes. This research offers valuable insights for developing efficient and robust thermal protection systems for turbine blades.

Presenting Author: Huihui Wang Xi’an Jiaotong University

Presenting Author Biography: Huihui Wang is currently a Ph.D. candidate in Xi'an Jiaotong University. His research focuses on gas turbine cooling technology and heat transfer mechanisms, with specific interests in advanced cooling techniques for turbine blades.

Authors:

Huihui Wang Xi’an Jiaotong University
Yang Chen Dongfang Turbine Co., Ltd., Dongfang Electric Corporation
Qinghua Deng Xi’an Jiaotong University
Anqi Liu Xi’an Jiaotong University
Zhenping Feng Xi’an Jiaotong University