oj.bulmer 
February 28, 2013 12:19 
Grid refinement ratio for unstructured mesh
Hello,
I am trying to streamline the mesh independence practices using Grid Convergence Index and Richardson Extrapolation as they are considered the best in practical CFD. (Ref: Roache, P. J. "Perspective: a method for uniform reporting of grid refinement studies." TRANSACTIONSAMERICAN SOCIETY OF MECHANICAL ENGINEERS JOURNAL OF FLUIDS ENGINEERING 116 (1994): 405405.)
Now, element sizes for the consecutive meshes should be known to get the grid refinement ratio used in the calculations in this procedure. But since we use unstructured mesh along with the extruded mesh; I am not sure if the value of element local element size (in the important regions of high gradients) is representative of the size for that particular mesh.
Roache suggests the following formula for grid refinement ratio for unstructured meshes, using their elementcounts and :
Now, he defines D as Dimensionality. What does it mean and how to calculate it from the fluid domain?? :confused:
Thanks
OJ
