Periodic oscillations observed in swirling flows with and without combustionData obtained by laser induced Rayleigh scattering and hot-wire anemometry are used to study periodic oscillations in swirling flows with and without combustion present. Power spectral density functions reveal the presence of energetic, periodic oscillations in the flow. A band of low frequency oscillations (25-100 Hz) is observed on and near the centerline in the presence of a recirculation zone and is attributed to axial oscillations of the recirculation zone which are amplified with combustion by an interaction between the mechanism for flow recirculation and flow changes induced by combustion. High frequency oscillations between 300-500 Hz are observed in an annular region located in the vortex core. A stability analysis is performed, and it is concluded that these oscillations are most likely helical waves resulting from hydrodynamic instability in the vortex core upstream of the test section.
Document ID
19860038017
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Gouldin, F. C. (Cornell Univ. Ithaca, NY, United States)
Halthore, R. N. (Cornell Univ. Ithaca, NY, United States)
Vu, B. T. (Cornell University Ithaca, NY, United States)