An alternative method to adjust the mass of an element set is to specify a
scale factor. When the mass adjustment is defined using a scale factor, you can
maximize the minimum stable time increment in the initial configuration for an
element set by redistributing either the total mass or only the added mass
among the elements in that set. The redistribution of the total mass to
maximize the time increment is done iteratively by taking mass from each
element with a stable time increment greater than the average and adding it to
the elements with lower time incrementsâ€”this iterative process stops when all
elements have the same time increment within a tolerance.

The redistribution of only the added mass to maximize the time increment is
done in a similar fashion, but only the added mass is transferred between
elements. The elements may not have the same time increment after the
redistribution is complete. In this case the scale factor should be greater
than one. Both choices of mass redistribution described here affect the center
of mass and the principal directions of rotary inertia, but redistributing only
the added mass with a relatively small scale factor may have a lesser impact.

Alternatively, you can scale the mass to redistribute it uniformly (in
proportion with the pre-adjusted mass) without affecting the center of mass and
the principal directions of rotary inertia.

Input File Usage

Use one of the following options to maximize the time
increment by redistributing the total mass of the element set:

MASS ADJUST, TARGET DT=MAXIMIZE
elem_set_name, , , scale_factor, REDIST

MASS ADJUST
elem_set_name, , , MAXIMIZE, scale_factor, REDIST

Use one of the following options to redistribute only the
added mass:

MASS ADJUST, TARGET DT=MAXIMIZE
elem_set_name, , , scale_factor, ADD

MASS ADJUST
elem_set_name, , , MAXIMIZE, scale_factor, ADD

Use the following option to scale the mass for an element set
without altering its center of mass:

MASS ADJUST
elem_set_name, , UNIFORM, scale_factor