Experimental and numerical studies of the fuel concentration distribution within the near-wall area in a compact space for a gas turbine combustor

Interstage combustion is known for its small axial distance, high combustion efficiency and low lean blowout boundary. However, in a compact space, the distance between the fuel injection location and the wall is confined, and the high-temperature wall may affect the fuel distribution and in turn affect the combustion efficiency. In this study, an experiment of kerosene single-droplet evaporation was conducted, and the fuel distribution in an interstage combustor was numerically simulated. The experimental results showed that the evaporation rate of fuel droplets decreased with increasing distance from the high-temperature wall, and the influence of the lower wall on fuel evaporation was greater than that of the sidewall. The fuel evaporation rate at the high-temperature position within the nonuniform wall temperature field was relatively high. The numerical simulation results indicated that with increasing temperature, the effect of the wall on fuel evaporation increased, as did the uniformity of the fuel distribution. The direction of the temperature gradient imposed the greatest effect on the fuel distribution under nonuniform temperature conditions. This will facilitate the selection of the optimal ignition location within the cavity to achieve efficient combustion. Moreover, it's possible to control the fuel distribution by adjusting the wall temperature.