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The present paper reports on the combined stereoscopic particle image velocimetry (PIV) and planar laser induced fluorescence (PLIF) measurements of turbulent transport for model swirl burners without combustion. Two flow types were considered, namely the mixing of a free jet with surrounding air for different swirl rates of the jet (Re = 5 × 103) and the mixing of a pilot jet (Re = 2 × 104) with a high-swirl co-flow of a generic gas turbine burner (Re = 3 × 104). The measured spatial distributions of the turbulent Reynolds stresses and fluxes were compared with their predictions by gradient turbulent transport models. The local values of the turbulent viscosity and turbulent diffusivity coefficients were evaluated based on Boussinesq’s and gradient diffusion hypotheses. The studied flows with high swirl were characterized by a vortex core breakdown and intensive coherent flow fluctuations associated with large-scale vortex structures. Therefore, the contribution of the coherent flow fluctuations to the turbulent transport was evaluated based on proper orthogonal decomposition (POD). The turbulent viscosity and diffusion coefficients were also evaluated for the stochastic (residual) component of the velocity fluctuations. The high-swirl flows with vortex breakdown for the free jet and for the combustion chamber were characterized by intensive turbulent fluctuations, which contributed substantially to the local turbulent transport of mass and momentum. Moreover, the high-swirl flows were characterized by counter-gradient transport for one Reynolds shear stress component near the jet axis and in the outer region of the mixing layer.

This article presents the estimation of turbulent Schmidt number in a model gas turbine combustor. Different gases are used as the model fuel while maintaining the mass flow rate. The simplest closure models for Reynolds stress and turbulent flux are considered. The anisotropy of turbulent viscosity is demonstrated.

This paper was retracted by IOP Publishing on 03 December 2019. This paper was published due to a technical error and was not intended to be included in this journal. Retraction published: 03 December 2019.

This paper reports on experimental study of the flow in a model combustion chamber using planar optical methods. The flow was organized by model GT-premixer produced by JSC “EUC-Aviadvigatel”, Perm, Russia. The measurements were carried out in a cold flow without combustion at elevated pressure of 2 atm and air flow rate up to 0.5 kg/s. Acetone vapor was seeded to the flow as a tracer of model fuel. The distributions of local concentration were measured using planar laser-induced fluorescence approach. To measure velocity fields by particle image velocimetry technique, water-glycerol particles were introduced to the air flow. Two series of experiments were accomplished for design and off-design conditions. The pressure drop at the GT-premixer was the same for these two cases. The results for off-design conditions show that fuel concentration distribution drastically depends on the scheme of fuel supply.

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