An Inverse Method for the Determination of Thermal Stress-Intensity Factors Under Arbitrary Thermal-Shocks

The analysis of stress-intensity factors is of immense importance when designing vessels, pipes, and end-caps as well as supporting structures and plates seen in high-temperature applications. Given this importance and the difficulty of measuring actual thermal boundary conditions, a generalized series based on a new and infinitely differentiable polynomial was employed to inversely determine the transient temperature distribution in a semi-infinite slab using only a single temperature history. These temperature distributions were in turn used to find the potential crack-opening stresses throughout the body. Using the found stresses and a weight-function approach, stress-intensity factors were then determined for both edge and semi-elliptical cracks under an arbitrary thermal-shock. When compared to other methods for various thermal scenarios, the method showed good agreement for both edge- and semi-elliptical surface cracks.