Skip to main content

research

Multiple scattering theory for heterogeneous elastic continua with strong property fluctuation: theoretical fundamentals and applications

Submitted by hehuijing on
research

Scattering of elastic waves in heterogeneous media has become one of the most important problems in the field of wave propagation due to its broad applications in seismology, natural resource exploration, ultrasonic nondestructive evaluation and biomedical ultrasound. Nevertheless, it is one of the most challenging problems because of the complicated medium inhomogeneity and the complexity of the elastodynamic equations.

Ph.D. Student Positions in Computational Materials Science and Mechanics

Submitted by AnterEl-Azab on
research
dislocation dynamics
mesoscale plasticity
microstructure
phase field methods
Radiation effects in materials
Computational methods in Materials Science

Several Ph.D. student positions are available in Professor El-Azab’s group with the School of Materials Engineering, Purdue University. The group performs advanced theoretical and computational research in the areas of mesoscale plasticity and dislocation dynamics, radiation effects in materials, microstructure evolution, phase field method development, and computational methods for materials science and mechanics. Applicants with MS in mechanical, aerospace, or materials engineering, with background in microstructure science, continuum mechanics and elasticity, numerical methods or computational techniques such as finite element method are highly preferred. Knowledge of at least one advanced programming language such as Fortran or C++ is required. Exceptional applicants with BS degree will also be considered. The openings are for spring 2018, summer 2018 and fall 2018. Applicants must meet Purdue University and School of Materials Engineering admission criteria. For inquiry please send email to Professor El-Azab (aelazab [at] purdue.edu).

In 1D wave propagation problem, how to find the curl of a given source function?

Submitted by Sundaraelangov… on
Forums
Computational Mechanics Forum
Choose a channel featured in the header of iMechanica
research

I am trying to solve 1-D wave equation by calculating potentials ϕandψxϕandψx for displacement field ux=∇ϕ+∇×ψux=∇ϕ+∇×ψ. I am trying to decompose my source function fxfx (such that fx=∇b+∇×hxfx=∇b+∇×hx) in terms of potentials bandhxbandhx, using which I can can compute ϕandψxϕandψx. While decomposing source term fxfx, trying to calculate bandhxbandhx, I have a problem/confusion in finding the curlcurl of hxhx. Please see the manual hand-written picture attached here 

On Weingarten-Volterra defects

Submitted by Amit Acharya on
research
continuum mechanics
defects
disclinations
dislocations

Amit Acharya

(in Journal of Elasticity)

The kinematic theory of Weingarten-Volterra line defects is revisited, both at small and fi nite deformations. Existing results are clari fied and corrected as needed, and new results are obtained. The primary focus is to understand the relationship between the disclination strength and Burgers vector of deformations containing a Weingarten-Volterra defect corresponding to di fferent cut-surfaces.

Discussion of “Measuring and Understanding Contact Area at the Nanoscale: A Review” by Tevis D. B. Jacobs and Ashlie Martini

Submitted by Antonio Papangelo on
research
adhesion; contact mechanics; rough contact

M. Ciavarella(1) and A. Papangelo(2)

(1) Politecnico di BARI, Center of Excellence in Computational Mechanics, Deparment of Mechanics, Mathematics and Management. Viale Gentile 182. 70125 Bari (Italy)

(2) Hamburg University of Technology, Department of Mechanical Engineering, Am Schwarzenberg-Campus 1, 21073 Hamburg, Germany

michele.ciavarella [at] poliba.it, antonio.papangelo [at] poliba.it

How to Realize Volume Conservation During Finite Plastic Deformation

Submitted by Bin Liu on
research
Plasticity

Volume conservation during plastic deformation is the most important feature and should be realized in elastoplastic theories. However, it is found in this paper that an elastoplastic theory is not volume conserved if it improperly sets an arbitrary plastic strain rate tensor to be deviatoric. We discuss how to rigorously realize volume conservation in finite strain regime, especially when the unloading stress free configuration is not adopted in the elastoplastic theories.

Mechanical Reading of Ferroelectric Polarization

Submitted by Amir Abdollahi on
research

The mechanical properties of materials are insensitive to space inversion, even when they are crystallographically asymmetric. In practice, this means that turning a piezoelectric crystal upside down or switching the polarization of a ferroelectric should not change its mechanical response. Strain gradients, however, introduce an additional source of asymmetry that has mechanical consequences.

Subscribe to research