Stress on the fluid, and pi tensor


I would like to calculate the wall shear stress on a bioreactor. I will use the fonction “computeStress(pi)”, but in the pdf documentation, there isn’t the explanation of the pi tensor, while there is a (1) nearby the greek letter pi.

In 3D there are 6 components, so what are they ? Maybe there is a documentation about this.

Thanks a lot.


you are right, in 3D there are 6 independent component to the stress tensor. You can find the ordering of the components in OpenLB in the util.h file at line 247 (note that above there is the ordering for the 2D case). I hope I answer your question (I’m not completely sure…).

Ok, I’ve found. Thanks a lot

For others :

namespace tensorIndices3D {
enum { xx=0, xy=1, xz=2, yy=3, yz=4, zz=5 };