Characterization of Advanced Combustor Cooling Concepts for Metallic and Oxide Ceramic Matrix Composites in a Reacting Flow

Abstract

Effusion cooling is a promising approach to cool especially the walls of lean combustors where the cooling air consumption is to be reduced significantly. Due to the velocity distribution and cooling air pressure drop in a combustor the effectiveness can be further increased by reducing the cooling air momentum. Double skin designs like impingement effusion cooling provide a significant improvement but at the drawback of a complex and expensive manufacturing process. Different advanced cooling concepts offering a similar reduction of the cooling air jet momentum in a single skin design for metal and ceramic walls are characterized under realistic conditions. Lateral trenches as well as effusion holes with 90° turns are used. Their total cooling effectiveness is compared to a plain single skin effusion cooling concept. The metallic samples are manufactured using additive manufacturing offering additional degrees of freedom in the cooling design in comparison to conventional manufacturing techniques.