Stress Intensity Solutions of Thermally Induced Cracks in Combustor Liner Hot Spots Using Finite Element Analysis (FEA)

摘要

Developing stress intensity solutions for thermal strain inducing cracking in hot spots is the chief goal of this research. Using finite element analysis (FEA) to model the stress state and crack stress intensities resulting from thermal gradients, a model is needed to represent and predict this cracking and eventual crack arrest in combustor liners in turbine engines. In determining the number of cycles until the crack arrests, the model estimates the number of cycles within 5 when compared to the actual 462 experimental cycles run. While the K vs. a curve used for this estimation indicates a relatively high would-be Kth value, the model shows that repeated cycles at the same crack length would produce a lower, more accurate K level at the length that the crack arrests.