Cooling Performance Prediction of Turbine Blades and Vanes for Conceptual Design

Abstract The early design phases of an aero engine are crucial for its technical and commercial success. These phases involve iterative processes that encompass all major components and disciplines, and they lay the foundation for the subsequent development stages. The cooling of gas turbine blades and vanes is of utmost importance, as they represent the hottest and one of the mechanically highest-loaded components of an aero engine. In the mechanical conceptual design of a turbine, the design and weight estimation of the blades and vanes are significantly influenced by cooling. In the past, numerous simplified physical or statistical methods have been developed to calculate cooling air mass flow and cooling performance. However, many of these methods lack the simplicity or necessary details required for conceptual design or rely on input from experienced users for different cooling designs. To address these challenges, a new method has been developed for mechanical conceptual design. This method calculates the material temperature, cooling mass flow, and cooling performance of turbine blades and vanes. It can automatically select an appropriate cooling technique and calculate the cooling performance of a 0-dimensional blade at different operating points without the need for further user inputs. Additionally, models of different cooling techniques, a simulation of thermal barrier coating, and a new cooling mass flow calculation have been incorporated. This method has been applied to calculate the cooling performance of a stator vane in a one-stage high-pressure turbine (HPT). The results have been compared with data from existing literature. Furthermore, parameter studies have been conducted to analyze the influence of main gas temperature, cooling air temperature, and material temperature on the cooling mass flow. The findings indicate that for the HPT vane, a reduction of approximately 32% in the preliminary estimated cooling mass flow can be achieved by selecting a more advanced cooling technique, increasing the material temperature by around 8%, decreasing the main gas temperature by approximately 10%, or lowering the cooling air temperature by about 23%. This research was conducted in collaboration with MTU Aero Engines.