Measurement of spray/acoustic coupling in gas turbine fuel injectors

Abstract

A diagnostic to measure the acoustic coupling of air flow with a fuel injector spray has been developed and tested. The instrument measures the mass of fuel within a plane of the spray using planar laser-induced fluorescence. The signal is monitored continuously to measure mass flow fluctuations during acoustic excitation of the flow. A comparison with the acoustic signal provides a measure of the response/of the spray to acoustic excitation for a given nozzle design. This paper describes the approach to acquiring a planarintegrated time-dependent signal for response measurements. Results for several nozzle designs are also presented.