Liquid Fuel Modulation by Fluidic Valve for Active Combustion Control

Fluidic modulation of liquid fuel flow has potential as an actuator for active control of gas turbine engine combustors, improving thrust and emissions performance. This paper describes an experimental investigation into the feasibility of liquid fuel modulation using a bi-stable fluidic diverter for active combustion control. The results demonstrate that a practical bi-stable fluidic valve can be designed for the gas turbine combustor application, satisfying requirements for flowrate, pressure drop and tolerance to downstream pressure variations. A limiting frequency of approximately 100 Hz was obtained in this investigation, demonstrating that the flow capacity requirement sets the upper limit of the fluidic valve response. A suggestion for improving the frequency response is discussed.