Cubit 16.04 User Documentation
If the user needs fine control over mesh density, then for curvy or slanted sides of swept geometries, it is often useful to treat curves as if they had a different length when setting interval sizes. For example, the user may wish to specify that a slanting side curve and a straight side curve have the same "relative" length, despite their true length as shown in the following figure. These are not interval matching constraints; interval matching may change intervals so that the user-specified ratio does not hold exactly.
The relative lengths of curves are set with the following command:
{geom_list} Relative Length <size>
The following command is used to assign intervals proportional to these lengths:
{geom_list} Relative Interval <base_interval>
For a curve with relative length x, setting a relative interval of y produces xy intervals, rounded to the nearest integer.