In order to designate that a quantity is a design variable, you must first flag the quantity as a template entry in the same manner as when setting up a user-defined template (UDT). The following quantities are eligible to be design variables:
amplitude of displacement
When setting up mesh deformation, you can define the displacement of geometric entities (that is, volumes, surfaces, lines, and points) by specifying a direction and amplitude. For the purposes of die shape optimization, however, only the amplitude of the displacement is eligible as a design variable. By default, the initial value of a given design variable will be the value specified for the amplitude of the displacement during the mesh deformation setup.
the inlet flow rates
material data parameters
The viscosity, the relaxation times, the Arrhenius function parameters, and other viscoelastic parameters can be designated as design variables. Defining a material data parameter as a design variable is useful when you are employing a reverse engineering approach (see Example 100 in the Ansys Polyflow Examples Manual, which you can find on the Ansys Help site.
boundary condition parameters for a heat conduction problem sub-task
The quantities that can be design variables are:
the constant value for an imposed temperature
the parameters for an imposed flux density (
, 
, 
, 
, 
, and 
from Equation 13–7)
slip condition parameters
The quantities that can be design variables are:
the generalized Navier’s law parameters (
and 
from Equation 8–1) the threshold law parameters (
, 
, and 
from Equation 8–2) the asymptotic law parameters (
and 
from Equation 8–3) the approximate Arrhenius / Arrhenius law parameters, if the slip law is temperature dependent (
, 
, and 
from Equation 10–18 and Equation 10–20)
Note that the velocity of the wall (
in Equation 8–1, Equation 8–2, and Equation 8–3) cannot be a design
variable. concentration boundary condition parameters for a transport of species sub-task
The quantities that can be design variables are:
the constant value of an imposed mass fraction
the constant value of an imposed flux density
the constant value of an imposed potential boundary condition parameters for a potential problem sub-task
the constant value of the porous medium thickness (
in Equation 8–17) for a porous jump model sub-model the shell thickness for a heat conduction problem sub-model
There may be circumstances in which you want to link design variables, so that the
value of one is imposed on another. When this is the case, you can force an equality
between a "proxy" (
) and a “master" (
) design variable, such that:
 | (36–24) |
In this way, the proxy design variables are not seen by the optimizer either as
design variables or as equality constraints of the type 
. Consequently, the size and the complexity of the optimization
problem is reduced.
Typically, you should link design variables that are of the same kind. For example, you could impose the same amplitude of displacement on several topological entities that are not connected, or the same flow rate on several inlets. While it is possible in Ansys Polyflow to link design variables of different kinds (that is, you could impose the value of an amplitude of displacement on the rate of a flow inlet), such linkages should be avoided or used with care.
Note that a given master design variable may have more than one proxy. Also, you must not designate the same design variable as both a master and a proxy.
After you have flagged a quantity as a template entry, you must define the following design variable parameters:
name
Short names are recommended for design variables, for the sake of readability in the output files.
upper bound:
lower bound:
initial value
(optional) link with a master design variable through an equality