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Ph.D. opportunities in ME @ CU-Boulder

Submitted by Jianliang Xiao on
I am currently accepting applications for two Ph.D. students starting in Spring or Fall 2012. The students will join my research group (http://www.colorado.edu/MCEN/people/faculty/xiao.html ) in the Department of Mechanical Engineering at University of Colorado Boulder. 

Help for contact problem in tires

Submitted by pradeep632 on

HI

     I am trying to modeled a 3D tire assembly for a tire footprint. I assembled the tire, rim and the rigid-body as the road. I modeled the rim as an analytical rigid body. I am using STATIC GENERAL as the stpe with automatic stabilization. I have defined a following for the contact formulation in ABAQUS Standard:

1) Between the tire and road (analytical rigid-body):Surface to surface contact - Master surface: analytical rigid-body and Slave surface : the tire surface in contact with the rigid-body. The ineraction properties are:

Mode 2 stress intensity factor

Submitted by srisaika on

HI

I am working on mixed mode fracture mechanics project . I was wondering what would be the appropiate mesh size to calculate the SIF of Mode 2 accurately

 i am using ansys to calculate the SIF's .. I need the size of the mesh in terms of the radius of the first ring  of quadratic elements .

 some specifications of my project that might be helpfull

Crack size = .1 (curvilinear crack)

width = 5

karan

Coupled phase transformations and plasticity as a field theory of deformation incompatibility

Submitted by Amit Acharya on

(to appear in International Journal of Fracture; Proceedings of the 5th Intl. Symposium on Defect andMaterial Mechanics)

Amit Acharya and Claude Fressengeas

Force to Expel Water from Between Two Plates

Submitted by Helen A. A. on

Hello,



I was wondering if anyone knew the equation to find the necessary clamping force to expel a saline solution out from between two parallel plates. I would like the most general form of the equation if possible, but will provide more details if necessary.



Thanks!



:)



Helen

Effect of temperature on the stability of dielectric elastomers

Submitted by Bo Li on

Dielectric elastomer (DE) is a kind of electroactive polymer material,
capable of large deformation up to 380%. However, under conservative
operating conditions, DE is susceptible to instability with a small
deformation due to various modes of failure, including electrical
breakdown, electromechanical instability (EMI), loss of tension and
rupture by stretch. This paper proposes a free energy model in the
thermodynamic system of DE involving thermoelastic strain energy,
electric energy and purely thermal contribution energy to obtain the
stability conditions of all failure modes. The numerical results
indicate that the increase in temperature can markedly contribute to
improving the entropy production, the actuation stress and the critical

Time-averaged coarse variables for multiscale dynamics

Submitted by Amit Acharya on

(to appear in Quarterly of Applied Mathematics)

by Marshall Slemrod and Amit Acharya

Given an autonomous system of Ordinary Diff erential Equations without an a priori split into slow and fast components, we defi ne a strategy for producing a large class of `slow' variables (constants of fast motion) in a precise sense. The equation of evolution of any such slow variable is deduced. The strategy is to rewrite our system on an in finite dimensional "history" Hilbert space X and defi ne our coarse observation as a functional on X.