Conference article

This paper presents the methodology for performance optimization of a steam turbine cascade using CFD techniques for ORC (Organic Rankine Cycle) application. The steam turbine cascade is parameterized to achieve the maximum efficiency while using different organic fluids. The main objective of this work is to attain the maximization Cl /Cd ratio from a preliminary design. The approach to finding the maximum Cl /Cd ratio is based in optimization algorithms. The CRSA (Controlled Random Search Algorithm) was chosen for the optimization process. The optimization algorithm (CRSA) is integrated with CFD techniques, using automatic building schemes of parameterized geometries and meshes via “script files” with editing commands written in Tlc/Tk language, which will be interpreted by the commercial software ICEM-CFD®, in batch mode. Finally, for the numerical calculation, the commercial software FLUENT® is used with fluid properties, real gas model, turbulence model and boundary conditions set through “journal files”. In this paper, R245fa and Toluene are used as working fluids. Results of drag, lift and pressure distribution are reported. This methodology allows making corrections in the initial project of the cascade shape.

ORC, optimization, CFD, CRSA, turbomachinery, real gas, equations of state