Session: 12-14 Film cooling computational studies

Submission Number: 178701

Effect of Hydrogen Combustion on Film Cooling Performance of a 7-7-7 Shaped Hole 

This study numerically investigates the effect of hydrogen-enriched combustion on the film cooling performance of a 7-7-7 shaped hole. As a key strategy for decarbonization in power generation, hydrogen blending in gas turbines introduces significant aerodynamic and thermal challenges in the turbine section. One critical aspect is the alteration of film cooling effectiveness, which protects turbine components from high-temperature mainstream gases. The combustion of hydrogen blends modifies the composition and thermophysical properties of the mainstream gas, affecting the interaction between the mainstream and the coolant jets. To quantify these effects, the film cooling performance was evaluated under various mainstream conditions derived from combustion simulations with varying hydrogen blending ratios (HBR). The results indicate that with increasing HBR, the mainstream gas density decreases, while its specific heat and thermal conductivity increase. Unlike conventional cylindrical holes, which were previously reported to be susceptible to jet liftoff at high HBRs, computational fluid dynamics (CFD) simulations revealed that the 7-7-7 shaped hole significantly mitigates this liftoff phenomenon. The magnitude of performance variation with HBR was substantially reduced, although the overall trend was maintained. However, differences in discharge characteristics, such as the pressure ratio dependency, were still observed. In conclusion, while the 7-7-7 shaped hole offers enhanced resilience against bulk changes in mainstream properties, the nuanced shifts in its flow behavior suggest that further analysis of these secondary effects is crucial for fine-tuning its performance.

Presenting Author: Yoonhyeong Jeong Korea University

Presenting Author Biography: Yoonhyeong Jeong is a Ph.D. student in the Department of Mechanical Engineering at Korea University, Seoul. His research focuses on the aerothermal analysis of gas turbines, including heat transfer and aerodynamic losses, using computational fluid dynamics (CFD). He is currently specializing in the aerodynamic effects of gas property variations resulting from hydrogen combustion, utilizing high-fidelity simulations.

Authors:

Yoonhyeong Jeong Korea University
Uideok Lee Korea University
Jaiyoung Ryu Korea University