Session: 11-01 Combustor-turbine interactions

Paper Number: 126063

126063 - Investigation of Hot Streak Migrations in a Triple Dual-Stage Swirler Combustor Coupled With Turbine Vanes Under Different Contraction Ratios 

With the rapid development of modern gas turbines and aeronautical engines, the combustor outlet temperature is consistently escalating, leading to an intensified interaction between combustor and turbine. Meanwhile, the strong turbulence, residual swirl, and presence of hot streak at the combustor outlet exert considerable influence on the downstream turbine, notably affecting blade aerodynamics and heat transfer dynamics.

Nowadays, considerable research efforts are focused on the coupled system of combustor and turbine, aiming to elucidate the flow dynamics and migration patterns of hot streak under complex interactions. This work presents a setup consisting of a three-sector combustor and six turbine guide vanes (TGVs), equipped with advanced lean-burn triple dual-stage swirlers. Temperature distribution of the combustor outlet in the coupled system is measured through a high-temperature dual-axis displacement system. Also, Numerical works are conducted to unveil the initiation and progression of hot streak within the combustor, operating within the coupled system. Additionally, investigations focus on examining the impact of different contraction ratios on the mixing characteristics of gas and coolant within the combustor. Moreover, the migration process of hot streak in turbine guide vanes in the coupled system are studied.

Overall, numerical simulation shows a great agreement in the outlet temperature distribution with the experimental results, but overestimate the amplitude due to underestimation of the mixing effects. Furthermore, numerical results indicate that the influence zone of the TGVs on the pressure within the combustor can reach the position of the dilution holes, which significantly affecting both the depth and mixing characteristics of the diluting jet. As the contraction ratio increases, a rise in the outlet temperature distribution factor (OTDF) within the combustor is observed, attributed to diminished mixing effects. Conversely, at the TGVs outlet, an augmented flow velocity and enhanced mixing effects in the TGVs’ flow channel contribute to a more uniform temperature field. Furthermore, clocking position of TGVs under the conditions of this work is found to hinder the mixing of coolant in different flow channels. which highlights the significance to establish a correlation between TGVs’ clocking position and the inlet hot streak.

Presenting Author: Jiacheng Lyu Zhejiang University

Presenting Author Biography: Jiacheng Lyu is a PhD student in the Advanced Power and Thermal Fluids Laboratory of Zhejiang University. His research interests include combustor and turbine interaction, combustion dynamics.

Authors:

Jiacheng Lyu Zhejiang University
Keqi Hu Zhejiang University
Zhixin Zhu Zhejiang University
Gaofeng Wang Zhejiang University