[XIAJINXIA]

In the Ansys CFX model, how to obtain the variable of the maximum edge length of local grid if it is needed in the model modification.

[ghorrocks]

You can get mesh statistics and define new variable fields which have mesh quality measures in CFD-Post on the calculator tab. Run the mesh calculator and the new variables will be generated.

[XIAJINXIA]

Can I get the variable with mesh statistics like maximum edge length of local grid in CFD-Pre?

[ghorrocks]

You cannot do it in Pre. From pre save a .cfx or .def file, load it into CFD-Post and you can calculate the mesh statistics.

[XIAJINXIA]

I have to get variable with mesh statistics like maximum edge length of local grid to modify the tubulence model,but i do not know how to define or get it.

[ghorrocks]

Have a look at the length variable. I am not sure which element length it contains but it might be useful.

But on a more fundamental level - any turbulence model which requires the mesh edge length as an input means it is probably not mesh independent. You would think a turbulence model should only have physical parameters as inputs.

[XIAJINXIA]

In CFX,Δmax is the maximum edge length of the local computational cell within DES models.How can i get the defined Δmax in CFX?

[ghorrocks]

You will need to activate the DES model for that to be available.

Have you looked at the "Mesh Length Scale" variable? I am not sure exactly what length it reports but it might be useful.

There is also the volume of the finite volumes. You could take the cube root of this to get a mesh length scale. This is variable "Volume of Finite Volumes".