Analysis and Modeling of Foreign Object Damage (FOD) in Ceramic Matrix Composites (CMCs)

The Phase I deliverable will be a physic-based model which represents a CMC gas turbine component concomitantly at the material level and the structural level. This model will be probabilistically analyzed to account for the uncertainties in material properties and the uncertainties in the size and impact velocities of possible foreign objects (FOD). A ceramic material must display sufficient capability to withstand the degrading effects that arise from external events such as FOD impacts. In addition to withstanding impact events, the CMC must be able to resist crack propagation through the thickness resulting from FOD induced surface flaws. Further issues of concern: 1) the possibility of impacting materials scratching off the environmental barrier coating (EBC) coating and the subsequent consequences. 2) Given constant environmental attack of a CMC combustor liner due to the vaporization of salty air/water, the rate and sizes of EBC debris that loosen and then impact on turbine nozzle guide vanes. The delivered phase I tool will provide the means to cost effectively investigate and resolve these issues in a phase II effort. An application demonstration problem is specified, such as a rotor blade or a vane.