Three different oxide/oxide ceramic matrix composite (CMC) materials are described. Design concepts for the attachment of the CMC component to the metal structure of the gas turbine are developed in a first work stream focused on the combustion chamber and the turbine seal segment. Issues like environmental barrier coating (EBC)/thermal barrier coatings (TBC), application and volatilization, allowance for the different thermal expansion and the mechanical fixation are addressed. The design work is accompanied by CFD and FEM simulations. A variation of the microstructural design of the three oxide/oxide CMC materials in terms of different fiber architecture and processing of matrix are considered. Also, mechanical properties of these variations are evaluated. The material concepts are developed further in a second work stream. The CMCs are tested in various loading modes (tension, compression, shear, off-axis loading) from room temperature to maximum application temperature focusing on tensile creep behavior. By modification of the matrix and the fiber-matrix interface as well as EBC coatings, the high temperature stability and the insulation performance are enhanced. An outline of the “High Performance Oxide Ceramic”-program HiPOC for the following years is given, including manufacturing of a high-pressure tubular combustor and turbine seal segments from the improved materials as technology samples, for which validation testing up to technology readiness level 4 is scheduled for 2011.

Effusion cooling is an advanced cooling concept for modern aeroengine combustors and offers a very stable convective coolant film along the wall combined with heat removal inside each hole. In order to find the best positions of the cooling holes, CFD calculations with conjugate heat transfer can be done to predict wall temperature distributions. An extensive CFD simulation with local grid refinement is required to evaluate near wall phenomena. A combustor with complex effusion hole pattern leads to large computational meshes for both the fluid and the solid increasing the computational costs. A helpful approach to speed up calculations is to replace the cooling holes by a set of new in-and outflow boundary conditions for virtual effusion holes. Computational costs and time for the design process can be saved. In the paper the cooling concept of a combustor liner with 368 virtual cooling holes is shown and the influence of the combustion near the wall is investigated. The combustion model used allows to account for kinetic effects in the near wall region.

Wall cooling in aero engine gas turbine combustors is one of the main issues in the development of advanced combustion concepts, especially for lean combustion technology. Here fuel is burned in a mixture with a lean equivalence ratio and the CO oxidation is prone to quenching effects caused by mixing processes between cooling film and reacting burner flow. The information about the distribution of CO concentrations is of great interest in such a configuration in order to increase the understanding of the impact of large scale mixing processes. Up to now planar laser measurements of the CO emissions within the flame region have not been realized under realistic operation conditions such as elevated pressure. A new planar and quantitative CO LIF measurement technique has been developed for measurements especially at elevated pressures and first results are presented in this contribution. Numerical simulations have been performed to support the measurements.

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