Gas temperatures in aero-engine combustors can reach 2500K, considerably higher than the allowable temperatures for typical combustor wall materials. At the same time the temperature of the cooling air reaches 900K at full power conditions. Consequently there is only a small temperature difference available for cooling. Hence efficient cooling concepts for the combustor walls are required.
Lean-burn combustors are designed to significantly reduce emissions of nitric oxides, but
are especially challenging with respect to wall cooling. In lean combustion the air flow distribution is strongly modified in comparison to conventional combustors and less air is available for cooling.
The combustor department works on cooling concepts for both metallic and ceramic wall materials.
The combustor cooling activities are based on numerical and experimental research. Apart from numerical simulations, experiments at realistic operating conditions are essential for the understanding of the aerodynamic and thermal process as well as for the design of cooling concepts. For these experiments a high pressure cooling rig (HPCR) is operated. In addition the results are used to validate correlations derived on atmospheric test rigs and numerical simulations.
Wall temperature distribution measured with IR camera