High efficient steam turbine design based on automated design space exploration and optimization techniques

Due to the world-wide increasing demand for energy and the simultaneous need in reduction of CO2 emissions in order to meet global climate goals, the development of clean and low emission energy conversion systems becomes an essential and challenging task within the future clean energy map. In this paper the design process of a highly efficient large scale USC steam turbine is presented. Thereby, automated design space exploration based on an optimization algorithm is applied to support the identification of optimal flow path parameters within the preliminary and the detailed design phases. The optimization algorithm is first integrated with a 1D-mean line design code to automatically identify the optimal major turbine layout in terms of number of stages, reaction degrees, flow path geometry and basic airfoil parameters. Based on a progressive multi-section optimization coupled with a parametric airfoil generator and a CFD code, the profile shapes of each airfoil row are adapted to local flow conditions and systematically optimized to minimize aerodynamic losses in each turbine stage. A final 3D flow simulation of one representative optimized stage confirms the achievement of a highly efficient steam turbine design that fulfills both climatic and economic requirements.