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WEBINAR - How TURBOdesign Suite enables pump designers to meet emission legislation | Wed 9 March

In order to meet emission legislation such as EU’s Ecodesign directive or US’s Energy Conservation Standard for Pumps, pump designers need to optimize the efficiency of the pump over multiple operating points. In this 1 hour free webinar we will show how the different modules available in TURBOdesign Suite, especially the 3D inverse design code TURBOdesign1 and automatic optimization platform TURBOdesign Optima can be used to rapidly design high performance pump stages that meet requirement at multiple operating points.


Usermat: Linear viscoelastic model with geometric nonlinearity

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I have implemented a linear viscoelastic model using the user subroutine Usermat in Ansys.
I have used the classical paper: "Formulation and implementation of three-dimensional viscoelasticity at small and finite strains" of Kaliske & Rothert (Simo's approach) and it works fine for small deformations.

It is written in the documentation that in the case of a simulation with large strain (geometric nonlinearity), one must rotate the state variables.

tchuhong's picture

Positions for Research Assistant, Research Associate, PhD student or Postdoctoral Fellow at the Hong Kong Polytechnic University

We are looking for candidates who have strong background in mechanics to help us modelling and simulating of 2D and 3D nonconventional textile structures with negative Poisson’s ratio (auxetic textiles). The positions can be Research Assistant, Research Associate, PhD student or Postdoctoral Fellow depending on applicant’s previous experience.


Shailendra's picture

ASME 2016 IMECE- Call for Papers [Track 12] 12-35 Physics and Mechanics of Ductile Failure: Modeling and Experiments

We invite you to participate at our session on Physics and Mechanics of Ductile Failure: Modeling and Experiments at ASME 2016 IMECE to be held in Phoenix, Arizona, USA during November 11-16, 2016.


The deadline for submission of abstracts is March 7, 2016. The session is organized under Track 12,  #12-35 Physics and Mechanics of Ductile Failure: Modeling and Experiments.


mohsenzaeem's picture

The anisotropy of hexagonal close-packed and liquid interface free energy using molecular dynamics simulations based on modified embedded-atom method

This work aims to comprehensively study the anisotropy of the hexagonal close-packed (HCP)-liquid interface free energy using molecular dynamics (MD) simulations based on the modified-embedded atom method (MEAM). As a case study, all the simulations are performed for Magnesium (Mg). The solid-liquid coexisting approach is used to accurately calculate the melting point and melting properties. Then, the capillary fluctuation method (CFM) is used to determine the HCP-liquid interface free energy and anisotropy parameters.

Peng-Cheng Ma's picture

Positions for PhD students

Two positions for PhD students are available in Prof. Peng-Cheng Ma’s group in The Xinjiang Technical Institute of Physics and Chemistry, Chinese Academy of Sciences (CAS). The institute is one of the research unites affiliated to the Chinese Academy of Sciences, and it locates in Urumqi, China, a city with distinctively historic and cultural atmosphere. Major research activities in the group are: i) Carbon-based materials for structural and functional applications; 2) Polymer-based nanocomposites for engineering and environmental applications.

jingyun's picture



Lifeng Wang's picture

Faculty Position - Solid Mechanics - Stony Brook University

The Department of Mechanical Engineering at Stony Brook University has a tenure-track faculty position open in Solid Mechanics.

Required Qualifications: Ph.D. in Mechanical Engineering or related field.

Preferred Qualifications: Candidates in the area of Solid Mechanics, with emphasis on composite materials. An experimental background is preferred. Highly qualified candidates in other areas of solid mechanics will also be considered.

vrh59ir's picture

Local radial point interpolation (MLRPI) method for solving time fractional diffusion-wave equation with damping

The purpose of the current investigation is to determine numerical solution of time-fractional diffusion-wave equation with damping for Caputo's fractional derivative of orderα(1<α≤2).

Mac_Mechanics's picture

Inelastic behavior of geometrically nonlinear shell

Hi All,

I would like to know what would be the best reference to study inelastic behavior of nonlinear shell FEM and what are the current benchmark tests to validate its performance.

Thank you in advance.



Explicit vs. implicit FDM: Could you please suggest a reference?

The context is the finite difference modeling (FDM) of the transient diffusion equation (the linear one: $\dfrac{\partial T}{\partial t} = \alpha \dfrac{\partial^2 T}{\partial x^2}$).

Two approaches are available for modeling the evolution of $T$ in time: (i) explicit and (ii) implicit (e.g., the Crank-Nicolson method).

It was obvious to me that the explicit approach has a local (or compact) support whereas the implicit approach has a global support.

Sung Hoon Kang's picture

[Call for Papers] 3D Printed Soft Materials, ASME IMECE 2016

We would like to invite you to submit an abstract to the session on 3D Printed Soft Materials at the ASME 2016 IMECE to be held from November 11 to November 17, 2016 in Phoenix, AZ.

Additive manufacturing, also known as 3D printing, offers unique opportunities to explore novel properties and mechanics of soft materials. This session calls papers from research efforts related to soft materials with novel properties realized or created using 3D printing techniques. Specific topics of interest include, but not limited to:

Mac_Mechanics's picture

Plastic Behavior of Geometrically Nonlinear Shell

Hi All,

I would like to ask what would be a good benchmark test for evaluating the performance of plastic behavior of geometrically nonlinear shell?

Thank you in advance for you suggestions/comments.




oliver oreilly's picture

Updates to Online Resource on Rotations

The online resource on rotations, http://rotations.berkeley.eduhas been operational now for nearly 3 years.

My Top 10 Free 3D Model Databases

There are plenty of websites or repositories for 3D models. In practice I’ve often found myself searching through a lot of them when looking for a particular model. In my opinion, there isn’t a one stop shop solution. Instead, there are several really good websites that are worth to check out. In this post I’ll present my favorite 10 3D model databases divided into these four categories:

  • CAD models: If you are a mechanical engineer and are looking for models to re-use in your own design, then these repositories are for you.

Yonggang Huang's picture

A perspective paper on flexoelectricity by Prof. Pradeep Sharma

A perspective paper on flexoelectricity by Professor Pradeep Sharma (University of Houston) is published in the March (2016) issue of the Journal of Applied Mechanics.  A perspective paper describes an important, emerging field in mechanics.  The first perspective paper, by Professor Huajian Gao (Brown University), has been downloaded more than 8000 times since its publication.  This new paper by Professor Sharma is the 3rd perspective paper published in JAM.  The paper is attached.

Orthogonality and closure relations in Stroh formalism

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Orthogonality reationDear iMechanica members,

I deal with exteded Stroh formalism for piezoelectric media. I have problems with orthogonalization of Stroh´s matrices A, B, respectively how to fulfil the ortogonality relations (see attachments). I tried to "rape" it and made the left matrix inverse of the right matrix (then the product is an unit matrix) and I became very similar singularity expomemt as in the paper

PhD positions: (1) mechanics of porous media, (2) mechanobiology deadline extended

Announcing extension of the deadline of application for the two positions that I posted here last week. The deadline is now extended by one week to 21st February 2016.

Ramathasan Thevamaran's picture

A few experimental studies on the dynamic behavior of foam-like aligned carbon nanotubes

I'm posting a few experimental studies we have conducted on the dynamic behavior of hierarchical fibrous materials, using vertically aligned carbon nanotubes as a model material. I hope these will be useful to those who are interested in buckle-instabilities, multiscale behavior, and energy absorption mechanisms.

An overview:

Ravi-Chandar's picture

Special Volume of the International Journal of Fracture

As part of the celebration of the 50th Anniversary of the International Journal of Fracture, two special volumes were published in 2015. All articles of the 2nd 50th anniversary issue published in Nov/Dec 2015 are now freely accessible at the journal site until the 7th of April. These articles (and the ones published in the 1st 50th anniversary issue published in Jan/Feb 2015) provide reviews and perspectives on many aspects of fracture. You are welcome to browse thorough these articles and provide feedback on this blog!

Matlab source code for XFEM implementation (2D dynamic crack propagation problem)

Hello everyone,


I was looking for a Matlab source code for implementing XFEM to solve a dynamic problem (specifically dynamic crack propagation problem). I found several source codes which only solve static problems (they don't calculate mass matrix and they don't do the time integration). 


My research goal is to remove the oscillations from stress intensity factors  for a dynmic crack propagation problem. I will really appreciate any kind of help/suggestions.


With respectfully

Bhuiyan, A B M Abdul Ali

Shailendra's picture

Post-doctoral positions at National University of Singapore (NUS) and Singapore University of Technology and Design (SUTD)

Starting April 2016, we will have openings for two post-doctoral fellow positions in experimental and computational mechanics of advanced polymers. These positions will support a new research program between Singapore University of Technology and Design (SUTD) and National University of Singapore (NUS) funded by Agency for Science, Technology and Research (A*STAR). The project focuses on synthesizing, characterizing, modeling, and simulating the thermo-mechanical behavior of polymers with covalent adaptable networks (CANs), e.g. vitrimers.


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