In his recently published article in the journal of Computer Methods in Applied Mechanics and Engineering, CEE Colonel Harry F. and Frankie M. Lovell Endowed Professor Oscar Lopez-Pamies has developed a comprehensive, multi-level approach to aid in assessing the viability of any proposed computational model of fracture.
The article, titled "Nine circles of elastic brittle fracture: A series of challenge problems to assess fracture models", is co-authored with his Ph.D. student, Farhad Kamarei, and a colleague, Prof. John Dolbow from Duke University and one of his Ph.D. students, Bo Zeng and builds upon work funded by two grants from the National Science Foundation, one from the Applied Mathematics Program and the other from the Mechanics of Materials and Structures Program.
Figure summarizing the Nine Challenge Problems with the type of fracture nucleation and/or propagation phenomena that they probe. Courtesy: Oscar Lopez-Pamies
The article title is a nod to the "Nine Circles of Hell" in the literature classic The Divine Comedy by Dante Alighieri, alluding to the research that introduces a vetting process in the form of nine challenge problems, or an obstacle course, to assess the viability of models of fracture to be predictive. If a model passes all nine challenge problems, then it may be predictive; if it does not pass one of them, then it is guaranteed to be not predictive.
The problems provide a minimum standard that did not previously exist due to a lack of understanding of the fundamental material properties necessary to account for to model fracture. His recent work on fracture has identified such properties, including: i) the elasticity; ii) the strength surface, and iii) the toughness of the material.
Each challenge problem has been carefully selected with three key characteristics in mind. First, they all can be readily performed in a laboratory using standard testing equipment. Second, they lend themselves to an unambiguous analysis through a sharp description of fracture. Most importantly, this collection of problems spans the complete spectrum of well-established experimental findings on both the nucleation and the propagation of fracture that have been amassed over a century.
Given the multi-disciplinary importance of fracture, the work is expected to have a significant impact in all areas of engineering, science, and biology.
For more details on the research, and an in-depth discussion of the publication and its implications, listen to the podcast on Lopez-Pamies' website.