COMSOL Multiphysics™

multiphysics
TABLE 1-18: VALID PROPERTY/VALUE PAIRS
PROPERTY VALUE DEFAULT DESCRIPTION
Sdl Cell array of, or just
an integer vector or
all subdomains Only affect the indicated
subdomains in fem.equ
a NaN
Shrink off | on on Shrinks coefficients to
most compact form
Simplify off | on on Simplify expressions
The properties Diff, Outform, Outsshape, Rules, and Simplify can also be
specified by using fields in the fem structure. The default value for Diff is 'off' if
the resulting model has coefficient or weak form and 'on' if it has general form.
For calls of the form xfem1 = multiphysics(xfem,...), The properties Sdl/
Bdl/Edl/Pdl/Outsshape/Outform/Diff/Simplify can be given as cell arrays
indicating the properties’ values for the different elements of xfem.fem. In this case
the number of elements of the cell arrays giving the values must be the same as the
number of elements of xfem.fem. For Sdl/Bdl/Edl/Pdl/Outsshape, the value
NaN may be given if no value is actually intended to be passed.
For calls of the form xfem1 = multiphysics(xfem,...) Where the property Out
is specified, the value 'fem' means xfem1 as described above, but 'equ'/'bnd'/
'edg'/'pnt'/'dim'/'form'/'shape'/'sshape'/'border'/'var' are
returned as cell arrays containing these properties for each of the elements of
xfem.fem, and 'elemmph'/'eleminitmph' are concatenations of the individual
resulting properties.
Algorithm
The description below relates to the call fem1 = multiphysics(fem) unless
otherwise stated. The applications are specified as a cell array in the field appl in the
fem structure: fem.appl={a1 a2 ...}.
The notations ***, XXX and xxx used below means the fields equ, bnd, edg and/or
pnt. *** denotes any of these fields, XXX is used to denote the field which
corresponds to the largest dimension (usually equ), while xxx denotes the fields
corresponding to lower dimensions (usually bnd, edg, and pnt). Not all of them are
always present, rather their presence is dependent on the geometry of the domain
and the type of problem being solved.
304 | CHAPTER 1: COMMAND REFERENCE