PROFILED ENDWALL DESIGN USING GENETIC ALGORITHMS WITH DIFFERENT OBJECTIVE FUNCTIONS

摘要

Profiled endwalls are a widely researched technology for reducing the secondary loss in turbines. Most designs in the literature have been produced directly by manufacturers and although general performance information is given the detailed design decisions are kept confidential. This paper outlines a simple design system for profiled endwalls that uses genetic algorithms to find an acceptable design. As the design process is produced in an academic environment full details of the design process, geometries produced, objective functions and the various trade-offs involved in the design are available and discussed in the paper. Two designs were produced using the design system: one using secondary kinetic energy as the objective function of the design system and the second using a U-cubed integral. The different designs that are produced with the different objective functions are discussed in detail in the paper. Finally profiled endwalls have traditionally been used in the high pressure stages of gas turbine blades, the paper also discusses the merits and challenges in applying these technologies to the high pressure and intermediate pressure stages of steam turbines.