Calculate local strain tensor in a deforming 3D mesh


I’m trying to display local strain field in a deforming 3D mesh. My steps were as follows:

  1. Open .vtk files - Apply
  2. WrapByVector - Vectors: MeshDisplacement - Apply
  3. ComputeDerivatives - Settings as follows

And then I got this. I was wondering what those 0-8 options refer to. Is Strain0 eta_xx and Strain1 eta_xy? If so, I think it’s the result of global coordinates. Is there a way to compute the strain tensor in local coordinates (in the normal and tangent directions of each cell)?

Many Thanks,

That are the 9 components of a tensor

That’s right but for stress and strain tensors they are typically reduced to 6 components since σ_xy = σ_yx and so on. However, it’s possible that some software doesn’t do this, it all depends on the source of the data.