Features of a Cooling System Simulation Tool Used in Industrial Preliminary Design Stage

Abstract

Due to expected increases in gas turbine performance, strictly related to firing temperature, heat transfer is a major issue in design processes. To keep components temperature levels below design requirements, cooling systems are commonly used. Nowadays, nozzle and blade cooling systems have reached a high degree of complexity. In a preliminary design stage, both experimental and 3D numerical analyses are usually not very suitable to define geometry, coolant mass flow rate or cooling system typology. This is mainly due to the uncertainty on several parameters, i.e. pressure distributions and materials properties, and their undefined interaction. This work presents a simulation tool useful to provide system cooling development with qualitative and quantitative information about metal temperature, coolant mass flow rate, heat transfer and much more. This tool couples energy, momentum and mass flow conservation equations together with experimental correlations for heat transfer and pressure losses. Metal conduction is solved by two dimensional calculations for several blade to blade sections. This methodology allows to investigate several cooling system configurations and compare them in a relatively short time. Main features of this simulation tool are shown comparing obtained results with experimental data.