User login

You are here

research

Laura De Lorenzis's picture

French-German summer school on "Multiscale modeling of interfaces and avanced solution techniques"

The Graduate School MUSIC offers its second Summer School at the Leibniz Universität Hannover from 8 to 12 September 2014.  This year's summer school on “Multiscale modeling of interfaces and advanced solution techniques" is hosted by the Institute of Continuum Mechanics

Co-simulation engine error,

Choose a channel featured in the header of iMechanica: 

I am operating a co-simulation analysis in Abaqus. This a kind of interaction between fluid and solid so I am doing co-execution. Unfortunately, when the program run up suddenly I encounter this error "  Error in job Co-execution-3-Model-1: Co-Simulation errorError in job Co-execution-3-Model-2: The partner program in the co-simulation has issued a fatal error message.

ductility of carbon nanotube reinforced composites.

Choose a channel featured in the header of iMechanica: 

HELLO,

I want to know if carbon nanotubes reinforced composites are ductile as I want to do hydroforming process by using ABAQUS or any other metal forming process that can be implemented.

If it is formable than what are values of yeild strength, ultimate tensile strength, plastic strain,etc.

the matrix material is polymer(PmPV).

THANK YOU.

PhD in Mechanical Engineering at United States/United Kingdom/Canada

Im a final year student in Dual Degree(B.Tech in Mechanical Engineering and M.Tech in Intelligent Manufacturing). I want to procure PhD in manufacturing stream. Your suggestions on universities and areas of research are very valuable to me.

How to model fastener with same force-displacement behavior for all translational directions in a plane in Abaqus?

Choose a channel featured in the header of iMechanica: 

<p>Hi everyone. I want to model the fasteners connecting a wood sheathing to a steel frame in Abaqus. I want to input the same force-displacement behavior for all translational directions in the plane of the sheathing (like a radial spring). <br /> <br /> I was using spring element type Spring2 (nonlinear) but I could define behavior in only 2 translational directions in the sheathing plane (X and Z). This made my model overly stiff after the elastic range. I read about the RADIAL-THRUST connector element but it does not seem to be the one.

How to model fastener with same force-displacement behavior for all translational directions in a plane in Abaqus?

<p>Hi everyone. I want to model the fasteners connecting a wood sheathing to a steel frame in Abaqus. I want to input the same force-displacement behavior for all translational directions in the plane of the sheathing (like a radial spring). <br /> <br /> I was using spring element type Spring2 (nonlinear) but I could define behavior in only 2 translational directions in the sheathing plane (X and Z). This made my model overly stiff after the elastic range. I read about the RADIAL-THRUST connector element but it does not seem to be the one.

Adjal's picture

Contribution to dynamic behaviour of structures

Most of topics here in this web site treat the physical behaviour of materials, I would like to share my knowledge and my ideas concerned the analysis vibration of materials ( forced and free) for understand the mechanical behaviour of structures

I adress this message to  researcher whom interssting on dynamic of  structures 

Split Hopkinson Pressure Bar

Choose a channel featured in the header of iMechanica: 

Hello I am an undergraduate researcher working with a Split Hopkinson Pressure Bar and I'm new to this site. We recently changed from a set of 3/4" aluminum bars to a set of 1/2" aluminum bars and an interesting result occured. Our data collection system consists of a pair of strain gages midway along each bar.

Emilio Martínez Pañeda's picture

Numerical analysis of quasi-static fracture in functionally graded materials

This work investigates the existing capabilities and limitations in numerical modeling of fracture problems in functionally graded materials (FGMs) by means of the well-known finite element code ABAQUS. Quasi-static crack initiation and growth in planar FGMs is evaluated. Computational results of fracture parameters are compared to experimental results and good agreement is obtained. The importance of the numerical fit of the elastic properties in the FE model is analyzed in depth by means of a sensitivity study and a novel method is presented.

Mohammad Rouhi's picture

Composite Manufacturing Process Modeling Using Poromechanics

Modeling and simulation of manufacturing of advanced composite material is a must in today's industry as the use of advance composites is increasing dramatically. The aim is to reduce the number of trial and error by development of a simulation tool to model and predict the manufacturing fundamental phenomena happening simultaneously in different scales. Poromechanics is a multidisciplinary and multiphysics concept which can be used to achieve this goal.

R.Mehrabi's picture

Constitutive modeling of tension-torsion coupling and tension-compression asymmetry in NiTi shape memory alloys

A 3D constitutive model is proposed and verified with experimental data. Tension-torsion coupling effect and tension-compression asymmetry effect is investigate for tube shape memory alloy.

buckling of channel section

Choose a channel featured in the header of iMechanica: 
Free Tags: 

hi everyone,

 i am doing my dissertation on buckling of channel section. so i have used abaqus software to do the analysis. i did the modelling and applided unit load n given pinned-pinned end condition. and i have used constraints to both ends such that the load applied on the edge is concentrated at a point .

but the results i.e mode shapes are not coming properly even the eigen values are very less compaired to calculated buckling load.

plz help me out. 

dimensions of specimen channel section

width of web 100mm

width of flange 50mm

R.Mehrabi's picture

A thermodynamically-consistent microplane model for shape memory alloys

In this paper, a macroscopic model in a thermodynamically-consistent framework for shape memory alloys is proposed.

Baohong Chen's picture

Stretchable and Transparent Hydrogels as Soft Conductors for Dielectric Elastomer Actuators

       A soft ionic conductor can serve as an artificial nerve in an artificial muscle. A polyacrylamide hydrogel is synthesized containing a hygroscopic salt, lithium chloride. Two layers of the hydrogel are used as ionic conductors to sandwich a dielectric elastomer and fabricate a highly stretchable and transparent actuator. When the two layers of the hydrogels are subject to a voltage, the actuator reduces its thickness and expands. An areal strain of 134% is demonstrated.

Chris Yakacki's picture

Journal Club: Overcoming Challenges in Mechanically Actuating Liquid-Crystalline Elastomers

Smart materials are designed to have a controlled response to external stimuli. Shape-memory polymers (SMPs) are one of the most well known classes of mechanically active smart materials and have experienced an incredible amount of research attention over the last decade. They are able to recover programmed deformations when heated above a thermal transition; however, are generally considered a one-time event. Liquid-crystalline elastomers (LCEs) are another class of actively moving polymers; however, these materials can demonstrate reversible and repeatable shape memory without the need for “re-programming” after each actuation cycle.

Bo Li's picture

Electromechanical deformation of dielectric elastomer in two types of pre-stretch

A pre-stretched dielectric elastomer is capable of large deformation, when subject to voltage. This paper investigates the effect of two types of pre-stretch: by strain and by stress. The difference is compared and discussed using thermodynamics models. The significance of the pre-stretch in actuation is explained by examining the true stress in actuation. Under both pre-stretch strategies, during the actuation, the dielectric elastomer exhibits hysteresis loops due to snap-through but differs in shape and physical quantity.

Weijie Liu's picture

Plasticity integration: satisfaction of the consistency requirement

Dear all,

I am trying to formulate the return mapping algorithm with Hill48 yield condition, isotropic hardening law and flow rule referenced to Simo & Hughes (Computational Inelasticity).

In section 2.2.2.1, equation (2.2.9) expresses the Kuhn-Tucker complementarity conditions:

mohsenzaeem's picture

Shape memory effect and pseudoelasticity behavior in tetragonal zirconia polycrystals: A phase field study

Shape memory effect and pseudoelasticity behavior in tetragonal zirconia polycrystals: A phase field study, International Journal of Plasticity 60 (2014) 71–86. Martensitic tetragonal-to-monoclinic transformation in zirconia is a ‘‘double-edged sword’’, enabling transformation toughening or shape memory effects in favorable cases, but also cracks and phase degradation in undesirable scenarios.

Numerical approximation of tangent moduli

 

In this study, we presented a numerically robust procedure to evaluate 4th order tangent moduli which are vital for acheiving quadratic convergence of global Newton-Raphson scheme.

In this study, the proposed method is verified for hyperelastic models alone. However, the same can be extended to other constitutive models.

The paper can be found at

Numerically approximated Cauchy integral (NACI) for implementation of constitutive models

10.1016/j.finel.2014.05.016

Pages

Subscribe to RSS - research

Recent comments

More comments

Syndicate

Subscribe to Syndicate