This work details an integrative mechanical design process for combustion chambers. A major challenge in the development process of modern gas turbine combustors is to achieve low NOx emissions whilst ensuring the stability of the combustion process at all phases of the guaranteed operation regimes. The burner hardware plays a crucial role in determining emissions and maintaining a suitable aero- and thermo-acoustic performance of the combustion process. In addition, the burner hardware must be manufacturable at a reasonable cost. Efficient burner development requires a design process able to judge this behaviour at an early phase. This process must predict the combustor behaviour, the thermoacoustic mechanisms, the mechanical integrity as well as the life cycle of the burner. Based on the Alstom SEV (Sequential EnVironmental) burner for the reheat combustor of the GT24 gas turbine, this paper describes an exemplary process for the mechanical design, mechanical integrity, cooling and manufacturing. The acoustic aspects and the successful engine validation are addressed in separate papers.
The improved GT24 SEV burner has been developed with the following key features:
a) A Straight Mixing Zone aerodynamic design (SMZ) resulting in increased velocity and improved reactant pre-mixing
b) Multi-layered and braze constructed Front Panel design integrating combined and novel cooling and high frequency damping features
c) Optimised alloy selection for extended lifetime and improved manufacturability
In addition to the mechanical design and manufacturing process further details will be provided on aspects of cooling and mechanical integrity.