Simultaneous PIV and concentration measurements in a gas-turbine combustor model

Simultaneous velocity and concentration measurements have been performed in a gas-turbine combustor model. Particle image velocimetry (PIV) was used to acquire planar velocity information and to identify coherent flow structures. The Mie scattering technique, based on a slightly modified experimental setup, was used for concentration measurements in this mixing flow. The degree of mixing was assessed by examining local concentration measurements while inhomogeneously seeding the primary and secondary stream of the mixing layer. Connections between flow field and concentration distribution were highlighted using the proper orthogonal decomposition algorithm (POD). Uncertainties and systematic errors for the PIV measurements due to the suboptimal seeding are discussed using a comparison with a second test series at optimal seeding conditions. Results are presented for several flow parameters and at various lateral planes.