CFD Online Logo CFD Online URL
Home > Forums > OpenFOAM Programming & Development

Orthotropic solid displacement

Register Blogs Members List Search Today's Posts Mark Forums Read

LinkBack Thread Tools Display Modes
Old   November 4, 2010, 11:36
Default Orthotropic solid displacement
New Member
Daniel Chrastina
Join Date: Sep 2009
Location: Como, Italy
Posts: 7
Rep Power: 8
shpalman is on a distinguished road
Send a message via Yahoo to shpalman Send a message via Skype™ to shpalman
Hello all,

I'm trying to write a solver, loosely based on solidDisplacementFoam, which will work on orthotropic solids. The stiffness constants and the density are specified as fields (and there is also a misfit field f, since what I'm actually trying to do involves coherent interfaces between materials with different lattice constants).

Since the system is anisotropic I can't just calculate Lamé parameters, but since OpenFOAM can't handle the full fourth-rank 3x3 stiffness tensor I can't just write sigma = c : epsilon (where sigma is the stress tensor and epsilon is the strain tensor). However, since it's orthotropic I can work with vectors for the pressure and shear terms for both stress and strain, and two 3x3 tensors with the elastic constants in (for c_ij where i or j are 1, 2 or 3; and for c_kk where k is 4, 5 or 6).

rho * fvm::d2dt2(D) == fvc::div(sigma)

epsilon = 0.5*(fvc::grad(D) + fvc::grad(D)().T());



sigmaPressure = cPressure & epsilonPressure;
sigmaShear = cShear & epsilonShear;



I'm calculating the strain tensor from the displacement, setting up two strain vectors, getting two stress vectors from those via the stiffness tensors, and rebuilding the stress tensor which I'd like to put back on the right-hand side of the equation. But is it even possible to solve a system of equations like this, rather than having the spatial derivatives of D explicitly on the right-hand side?

I appreciate any feedback at all...


shpalman is offline   Reply With Quote


heteroepitaxy, semiconductor, soliddisplacementfoam, strain

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

Similar Threads
Thread Thread Starter Forum Replies Last Post
How model radiation of both solid wall and fluid£¿ Harry Qiu FLUENT 2 February 4, 2013 00:04
how to use Total Mesh Displacement for making a subject translating and rotating? snailstb CFX 3 September 16, 2009 04:06
Defining Solid Zones Not working elmcmaster FLUENT 3 May 22, 2009 07:14
Multiple Solid Domains - Interfaces Scott CFX 8 July 31, 2008 15:20
CFX4.3 -build analysis form Chie Min CFX 5 July 12, 2001 23:19

All times are GMT -4. The time now is 04:35.