Learning Forum

[Timothy Braun]

I would like to keep a report of the number of cells being limited by the solver (min/max Temperature, Turbulent Viscosity, etc). I know it is reported in the solver console, but I would like to plot these to see if the counts are going up or down or stagnant. Right now, I have limiter cell registers that track these cells.

Is there a way to use an expression to count the cells and send to a report plot? Or, is there an alternative easy way to do this? Or, must I use a UDF with a user-defined memory? If it's the last option, I might not bother.

[Rob]

Are you interested in cell count or region volume? The latter is available, Volume Report on a register. Otherwise have a look at your options re averages and sums. 

[Timothy Braun]

 

I am interested in the cell count, though maybe the total volume would be sufficient as a tracking parameter (effectively the same as a volume weighted count). I don’t know what data type a cell register is stored as with respect to Fluent expressions. (array of centroids?, big 1D list of boolean types for each cell id?, something else?) That information would make it a lot easier to constuct a sum or integral.

UPDATE (Solved):

Despite the name, using a “limiter” cell register wasn’t the option I wanted. It seems to return the total cell count in the domain. Instead, I created a field variable register:

Type: Cells Outside Range
Derivative and scaling: None
Iso-min and Iso-max set to the same as the solver limiter values.

Then, my expression was as follows (using placeholders for generality):

 

CountIf(register_name, [list of all cell zones cells in domain])

And I simply get what I wanted; a count of the number of cells being limited by the min/max temperature limit (set in the solver controls).

[Rob]

Not sure you need to worry about the data type, it's more a case of being creative with some of the report functions. No reason you can't divide/multiply reports to get a number to track.