ACTIVE OPTIMIZATION OF THE PERFORMANCE OF A GAS-TURBINE COMBUSTOR

ABSTRACT

A model natural gas–fired gas-turbine combustor is utilized to evaluate active optimization strategies. Sensors for exhaust species and reaction zone chemiluminescence are utilized with an adaptive fuel injection strategy in a closed-loop feedback control system. The feedback sensors consist of (1) traditional extractive probe-based exhaust measurements of CO and NO_x emissions and (2) chemiluminescence to provide very fast, yet accurate, indicators of performance. A direction-set algorithm is utilized to search for the region of optimal performance. The objectives of the study are to assess (1) the viability of controlling the spatial distribution for performance control; (2) the use of flame chemiluminescence as a fast, inferential emissions sensor for faster feedback; and (3) the robustness of the adaptive control strategy over the entire operability range and under a simulated perturbation mode. For the current study, a simulated injector perturbation scenario (partial fuel-jet blockage) is utilized to examine the robustness of the optimization strategies. The results obtained illustrate the relative correlation of the different sensor strategies with system performance and the ability of the closed-loop control to maintain combustion performance in light of a simulated hardware perturbation.

Keywords:

• active control
• combustor
• gas turbine
• natural gas
• sensor

This work was funded in part of the California Energy Commission, California Institute for Energy Efficiency, the U.S. Department of Energy Advanced Turbine Systems program, and the Southern California Gas Company. The efforts of Mr. Steve Hill are greatly appreciated for his assistance throughout the project.

Notes

The original version of this material was published by the Research and Technology Organization, North Atlantic Treaty Organization in Meeting Proceedings MP-051, “Active Control Technology for Enhanced Performance Operational Capabilities of Military Aircraft, Land Vehicles, and Sea Vehicles,” June 2001.