A method for predicting fatigue in notches utilizing CAE and the Theory of critical distances

​William Höglind and Simon Lundin present their master thesis titled "A method for predicting fatigue in notches utilizing CAE and the Theory of critical distances".
Students: William Höglind and Simon Lundin

Supervisors: Per Sjövall and Anders Ekberg

Examiner: Anders Ekberg

Opponent: Antonio Butkovic


When performing fatigue evaluations, the most critical areas governing the fatigue life of a component are geometrical discontinuities such as notches or sharp corners. Thus, accurate modelling of the geometric discontinuities and their effects is of highest importance to avoid catastrophic failures or overdimensioned components. Today, the fatigue evaluations are done utilizing CAE tools, such as FEA, to allow for more precise and complex calculations. The authors therefore investigated incorporating FEA with different approaches to fatigue in notches with the aim of producing a more accurate method. 
In this report, a methodology for predicting fatigue in sharp corners and notches have been developed. The proposed methodology stems from the Theory of Critical Distances and was verified against available fatigue test data, gathered from four different articles, with good correlation. The methodology was also expanded to allow for fatigue predictions of more complex geometries using virtual test specimen. 
Based on the results gained from the method validation it is clear that utilizing the proposed methodology and concepts would decrease overestimation of notches' severity, allowing for reduction in material usage as well as an enhanced ability to more accurately assess design ideas.​
Category Student project presentation
Location: M2 Newton, meeting room, Hörsalsvägen 7A, M-huset
Starts: 03 June, 2022, 11:00
Ends: 03 June, 2022, 12:00

Page manager Published: Mon 23 May 2022.