The role of primary jet injection on mixing in gas turbine combustion

The role of primary jet injection on the aerothermal structure and overall performance of a model gas turbine combustor is addressed in an experimental study. The impact of momentum ratio between the primary jets and the swirl air as well as the relative position of the jet row to the swirler injection plane are investigated in a combustor operated on propane at atmospheric pressure. The aerodynamic and thermal fields are characterized using laser anemometry and a thermocouple probe respectively. Species concentrations are acquired at the exit plane via extractive probe sampling. Four regimes are identified that describe the degree of interaction of the primary jets with, the swirl-induced recirculation zone. For each regime, the degree of jet penetration and entrainment in the recirculation zone and, as a result, the aerothermal structure of the dome region are substantially different. © 1991 Combustion Institute