The research work will discuss investigations into the characteristics of Low Swirl Injector (LSI) technique as a viable modification to be used in the conversion of liquid fuelled aero-engines to gaseous fueled gas turbines. Implementation of LSIs as an effective fuel injection method for in-operation gas turbines opens the possibility of conversion of liquid-fuelled jet engines to fuel-flexible aeroderivative gas turbine power plants. Low Swirl Injectors (LSIs) can be used for ultra-low emissions operation of gas turbines and promise to be a potential optimization tool in the conversion of jet engines to aeroderivative gas turbines, since their implementation requires minimal modifications to the combustor geometry.
The present study explores the fluid dynamics aspects of an LSI system that has been studied using a variable swirl burner, developed as a part of the study. The study included combustion experiments and cold-flow numerical simulations, in order to determine the limits of operation of the burner in the LSI regime. Further, a novel swirl number has been developed to better characterize the low swirl characteristics of the LSI technique. The LSI swirl number looks promising towards developing a deeper understanding of the physics of the LSI method, and opens up the possibility for new approaches to numerical modelling of LSI flames. The ultra-low emissions burning of LSI flames have been established in the experiments, thus showing with certainty that the Low Swirl Injection method has potential as a viable method for gas turbine combustor modification.
