Innovative Design, Structural Optimization and Additive Manufacturing of New-Generation Turbine Blades

TitleInnovative Design, Structural Optimization and Additive Manufacturing of New-Generation Turbine Blades
Publication TypeConference Paper
Year of Publication2020
AuthorsAmedei A, Meli E, Rindi A, Romani B, Pinelli L, Vanti F, Arnone A, Benvenuti G, Fabbrini M, Morganti N
Conference NameASME Turbo Expo 2020 Turbomachinery Technical Conference and Exposition
Date Published06/2020
PublisherASME
Conference LocationVirtual Event, September 21-25, 2020
Abstract

The need for high performances is pushing the complexity of mechanical design at very high levels, especially for turbomachinery components.

In this field, structural topology optimization methods together with additive manufacturing techniques for high resistant alloys are considered very promising tools, but their potentialities have not been deeply investigated yet for critical rotating components like new-generation turbine blades.

In this framework, this research work proposes a methodology for the design, the optimization and the additive manufacturing of extremely stressed turbomachinery components like turbine blade-rows. The presented procedure pays particular attention to important aspects of the problems as fluid-structure interactions (forced response and flutter phenomena) and fatigue of materials, going beyond the standard structural optimization approaches found in the literature. The new design strategy enables a substantial reduction of the component mass, limiting the maximum stress and improving the vibrational behaviour of the system in terms of eigenfrequencies, modal shapes and fatigue life.

Furthermore, the numerical procedure shows robustness and efficiency, making the proposed methodology a good tool for rapid design and prototyping, and for reducing the design costs and the time-to-market typical of this kind of mechanical elements.

The procedure has been applied to a low-pressure turbine rotor to improve the aeromechanical behavior while keeping the aerodynamic performance. From the original geometry, mode-shapes, forcing functions (due to rotor/stator interactions) and aerodynamic damping have been numerically evaluated and are used as input data for the following topological optimization. Finally, the optimized geometry has been verified in order to confirm the improved aeromechanical design.

After the structural topology optimization, the final geometries provided by the procedure have been then properly rendered to make them suitable for additive manufacturing. Some prototypes of the new optimized turbine blade have been manufactured from aluminum to be tested mechanically and in terms of fatigue.

Notes

GT2020-14418 (accepted for publication ASME J. Turbomach.)

Refereed DesignationRefereed