Assessing Cooling Insert Influence on Thermal Performance of Gas Turbine Cooling Systems

In today’s rapidly evolving industrial landscape, characterized by increasing demands for energy efficiency and environmental sustainability, the rising inlet temperatures of gas turbines pose significant challenges in their thermal design. This thesis, a collaboration between Politecnico Di Torino and EthosEnergy S.p.A., examines the performance of the cooling system within the first stage stator blades of industrial high-pressure gas turbines. Motivated by various design considerations, this study investigates two scenarios involving modifications in the height and position of the cooling insert. Computational fluid dynamics (CFD) simulations are conducted to analyze the influence of changed cooling insert heights on main parameters for the cooling system. Utilizing Ansys Fluent® for CFD analysis, this study systematically explores how changes in cooling insert height affect cooling system efficiency and thermal performance. Through a comprehensive investigation of internal and external airflow characteristics, including intricate interactions between cooling air and blade surfaces as well as the modified height of the cooling insert and mass flow rate, the research aims to provide valuable insights into optimizing cooling system design for enhanced thermal performance and durability. The cooling insert, an integral component within the gas turbine’s first stage stator blades, plays a pivotal role in managing internal temperatures. Acting as a conduit, it efficiently guides cooled airflow onto the internal surfaces of the blade, facilitating optimal heat dissipation. Additionally, the cooling insert directs airflow into channels designed to provide a film cooling effect, which effectively shields the blade’s surfaces from high temperatures, enhancing thermal performance and ensuring component longevity. The investigation reveals that reduced cooling insert heights subtly influence heat transfer dynamics and have a slight local effect on mass flow rate, contributing to a deeper understanding of cooling system optimization. Additionally, a simple design proposal is provided at the conclusion of the study to enhance thermal performance. This design serves as a foundational blueprint for future, more sophisticated cooling system designs, with the overarching goal of further improving efficiency and durability. In conclusion, this research significantly advances the understanding of cooling system performance in industrial gas turbine applications, thereby facilitating the development of optimized cooling solutions tailored for improved efficiency and longevity in a challenging industrial landscape.