Flow, heat transfer, and particle deposition in a novel corrugated impingement cooling channel with return holes: a numerical study

Enhancing the heat transfer performance and anti-deposition capability of turbine nozzle internal cooling channels is critical for improving aero-engine efficiency and service life. To alleviate crossflow-induced jet weakening in array jet impingement systems, a novel sinusoidal-corrugated jet plate with return holes is proposed. Numerical simulations are conducted to comparatively investigate the smooth jet plate (Baseline), the sinusoidal-corrugated plate (CJP), and the corrugated plate with return holes (CJP_RH) in terms of pressure losses, target wall heat transfer, and particle deposition characteristics. The effects of jet-to-target spacing ( H/d _j = 1–3), and particle diameter ( d _p = 1–20 μm) are also systematically examined under a typical jet Reynolds number Re = 15,000. The continuous phase is solved using the RANS method, while particle transport and deposition are simulated via the DPM coupled with the OSU deposition model. A dynamic mesh technique is further employed to capture the deposition evolution and its impact on heat transfer. Results show that the accumulated crossflow not only reduces the mass flow rate of upstream jets but also deflects downstream jet trajectories, thereby weakening the jet impingement cooling. The CJP and CJP_RH cases enhance the area-averaged Nusselt number while reducing pressure losses by optimizing the jet-to-crossflow interactions. At H/d _j = 1.0, the overall thermal performance factor is improved by 22.8% and 45.6%, respectively, while at H/d _j = 3.0, the corresponding enhancements are 7.1% and 8.8%. Furthermore, the deposition efficiency does not vary linearly with particle diameter but reaches a maximum at d _p = 5 μm. In contrast, the deposition efficiency of the CJP_RH case is less sensitive to variations in H/d _j , resulting in reductions of 27.6% and 46.1% compared with the Baseline case at H/d _j = 2.0 and 3.0, respectively. In addition, the dynamic evolution of deposits also confirms the superior performance of the CJP_RH case in terms of local peak accumulation.