Analysis of Multi-Stream Fuel Injector Flow Using Zonal Proper Orthogonal Decomposition

The 3-component velocity distribution of two lean-burn gas turbine fuel injectors are measured at a planar location near and parallel to the injector outlet. nominally same design, but one features blocked central passages study effects presence multi-streams reveal single stream characteristics embedded within multi-stream configuration. Stereoscopic particle image velocimetry is used in an isothermal, non-reacting water analogue flow facility engine relevant Reynolds number. data analysed using proper orthogonal decomposition (POD) work introduces concept Zonal POD. This splitting field into zones prior calculation POD modes better identify prominent structures associated with each zone. Because sorted by area averaged energy contribution, zoning interest may change individual will almost certainly their order for anything other than trivial fields. Analysis ensemble average fluctuation profiles reveals radial shift outboard mains pilot as well general increase RMS across intermediate region between flows. temporal coefficients frequency domain low-frequency peak evident region, which be affected flow. Furthermore, application ZPOD technique results closer representation given number modes. shows behaviour unsteady that significant proportion fluctuating energy, RMS, caused this characteristic.