crack

A Postdoctoral fellowship is available at The Johns Hopkins University, Baltimore, U.S.A. in the area of fracture and fragmentation under dynamic loading conditions. The potential candidate should have a Ph.D. in an engineering discipline, a strong background in fracture mechanics and extensive computational modeling experience working with the finite element methods or some other numerical method with application to solid mechanics.

Self-positioned nanomembranes such as rolled-up tubes and wrinkled thin films have been potential systems for a variety of applications and basic studies on elastic properties of nanometer-thick systems. Although there is a clear driving force towards elastic energy minimization in each system, the exploration of intermediate states where specific characteristics could be chosen by a slight modification of a processing parameter had not been experimentally realized.

In phase field method how one can specify the crack in fixed grid?



In case of finite element method one uses two overlapping nodes to model crack, which nodes separate after crack propagation. In case of phase-field, generally people use fixed grid finite difference method. My question is how the same node point can show two different displacements when crack has passed through it like FEM?

Macroscopic
cracks do not appear as a result of an ideal separation of two adjacent atomic
layers. Just the opposite, cracks appear as a result of the development of
multiple micro-cracks triggered by the massive breakage of atomic bonds. The microcracking
and the bond breakage are not confined to two neighbor atomic planes: the
process involves thousands atomic planes within the representative characteristic
volume of size h. This size defines the width (not the lenth) of the damage
localization zone and it can be called the crack thickness. The knowledge of