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Engineering Sciences 241: Advanced Elasticity

Submitted by Zhigang Suo on

This is a second graduate course in solid mechanics, and explores coupled mechanical, thermal, electrical, and chemical actions.  The course draws heavily upon phenomena in soft materials.

This page is updated for ES 241 taught in Spring 2020 (Maxwell Dworkin 221, T/Th 1:30pm-2:45pm)

The course taught in the past:

Solution of system of Differential equations

Submitted by Sandip Haldar on

Dear Wei and Mogadalai,

As mentioned earlier I am trying to solve for a vector {x} from

{x'}=[A(t)]{x}

where [A(t)] is known matrix of size (2X2) at the max 4x4, elements and are functions of "t".

{x} is a vector (nX1) function of 't'

{x'} is derivative of {x} with respect to 't'.

PhD and Postdoctoral Scholarships in Theoretical Modelling and Numerical Simulation of Snow Avalanche, Austria

Submitted by Mschneid on

University of Natural Resources and Applied Life Sciences, Vienna, Austria

A three-year fully funded PhD and a two-year postdoctoral scholarships are available immediately within a research project financed by the Austrian Science Foundation (FWF).  

The project deals with the theoretical modelling and numerical simulation of snow avalanches. Some emphasis is given to the interaction between snow avalanches and protection structures. The research of the applicants will include the further development of the theoretical model and the numerical analysis aimed at optimizing obstruction geometry and arrangement of snow protection. We expect candidates from one of the following research fields: physics, mathematics, engineering science, particularly fluid mechanics. The candidates should have a strong theoretical or numerical background, and proficiency in English.  

Stress analysis of adhesive layer in a sandwich specimen

Submitted by Mingji Wang on

I just came across the lecture notes from Professor Nix on Mechanical Properties of Thin Films. It is very educative and helpful. I wonder if anyone could recommend some analytical derivation on the stress of the adhesive layer between two similar/dissimilar adherends (sandwiched specimen) under mechanical or thermal loading.

Many thanks ...

Phase field simulations of polarization switching-induced toughening in ferroelectric ceramics

Submitted by Jie Wang on

Polarization switching-induced shielding or anti-shielding of an electrically permeable crack in a mono-domain ferroelectric material with the original polarization direction perpendicular to the crack is simulated by a phase field model based on the time-dependent Ginzburg-Landau equation. The domain wall energy and the long-range mechanical and electrical interactions between polarizations are taken into account. The phase field simulations exhibit a wing-shape- switched zone backwards the crack tip.

"Wrinkled hard skins on polymers created by Focused Ion Beam", PNAS , January 2007

Submitted by Ashkan Vaziri on

A stiff skin forms on surface areas of a flat polydimethylsiloxane (PDMS) upon exposure to focused ion beam (FIB) leading to ordered surface wrinkles. By controlling the FIB fluence and area of exposure of the PDMS, one can create a variety of patterns in the wavelengths in the micrometer to submicrometer range, from simple one-dimensional wrinkles to peculiar and complex hierarchical nested wrinkles. Examination of the chemical composition of the exposed PDMS reveals that the stiff skin resembles amorphous silica. Moreover, upon formation, the stiff skin tends to expand in the direction perpendicular to the direction of ion beam irradiation. The consequent mismatch strain between the stiff skin and the PDMS substrate buckles the skin, forming the wrinkle patterns. The induced strains in the stiff skin are estimated by measuring the surface length in the buckled state. Estimates of the thickness and stiffness of the stiffened surface layer are estimated by using the theory for buckled films on compliant substrates. The method provides an effective and inexpensive technique to create wrinkled hard skin patterns on surfaces of polymers for various applications. Click here for access to the full article. See also the press release: Applied scientists create wrinkled 'skin' on polymers

Summer Internship at Sandia National Labs, Livermore, CA

Submitted by Jonathan Zimmerman on

Sandia National Laboratories, California has established the Engineering Sciences Summer Institute (ESSI) program, in which applied mechanics, structural analysis and mechanical engineering graduate students are invited to spend a summer at SNL/CA performing research that would jointly benefit the students and Sandia. The program is nine years old and a description of the program is attached. Because of the funding base for this program, we can only consider students having U.S.