On Key Features of the AEV Burner Engine Implementation for Operational Flexibility

Abstract

Modern gas turbine combustors have to fulfill two major requirements. On the one hand they have to provide reliable operation with low emissions; on the other operational flexibility is of utmost importance. Alstom’s new AEV (Advanced EnVironmental) burner — an evolution of the proven EV burner technology — is one key feature to fulfill both on engine level. It can be operated on fuel gas and oil. In order to achieve low NOx emissions, modern combustors are operated in lean-premixed mode which is prone to thermoacoustic instabilities. This is accounted for by the implementation of multi-volume dampers. These dampers feature high damping performance in a broad low-frequency range thus widely enlarging the operating window. During transient operation, especially when switching from gaseous to liquid fuel and vice versa, the specific switching procedure with sophisticated fuel flow control schemes allows for a very smooth transmission. Another very important aspect is the optimization of leakage and cooling air into the combustion chamber. In order to validate the reduction of both, multiple thermal paint applications for fuel gas and oil operation in the full scale engine were performed at different engine loads up to baseload. In this paper, the AEV burner, broadband acoustic dampers, optimized cooling and leakage schemes, as well as innovative fuel switchover and operation concepts are described. It is shown that the combination of all of them makes the GT13E2 outstanding in fuel and operational flexibility featuring low emissions over the whole operating window.