A cold-flow experimental and numerical study of fuel injector nozzle and combustor chamber dynamics with swirl and non-swirl flows

摘要

The United States Department of Energy's Federal Energy Technology Center (FETC) has developed a bench-scale atmospheric coldflow rig to study the dynamic response of a premix fuel injector to pressure oscillations. A variable speed rotating disk was used to perturb the flow in the rig to simulate instability. Fuel injector nozzles of different lengths, and with and without swirling flows were tested. This paper presents the preliminary results on the dynamic pressures and velocities at the nozzle and the chamber interface. Phase-averaged velocity and pressure measurements indicate frequency doubling in the nozzle under harmonic and sub-harmonic excitations. This frequency doubling is also observed in the numerical computation results.