Experimental Investigation of Global Combustion Characteristics in an Effusion Cooled Single Sector Model Gas Turbine Combustor

Abstract

This paper presents experimental investigations in an effusion cooled single sector gas turbine combustor under close-to-reality boundary conditions, i.e. elevated pressure and combustor inlet temperature, under varying staging conditions. Flow field, flame structure and gas-phase temperature measurements are performed using particle image velocimetry (PIV), planar laser induced fluorescence of the hydroxyl radical (OH-PLIF) and coherent anti-Stokes Raman scattering (CARS), respectively. Additionally, isothermal mixing of the pilot and main stage is investigated using Acetone-PLIF. The influence of the pilot on the measured quantities can be identified up to 30 mm downstream of the burner head plate. These measurements are conducted within a novel test rig dedicated to the investigation of swirl-stabilized pressurized flames and effusion-cooling. The rig features full optical access for non-intrusive laser diagnostics from three sides and a modular effusion liner geometry. Important process parameters can be controlled independently in a wide range, providing a high versatility and reliability in terms of boundary conditions. Oxidizer and cooling air mass flows can be conditioned independently to 773 K and 973 K, respectively. Fuel staging can be gradually varied between 0% (fully premixed) and 100% (pilot only) at thermal loads up to 150 kW and a maximum pressure of 1,0 MPa. A movable block radial swirler allows for varying geometrical swirl numbers.