In the Goals and Constraints PropertyManager, you
set the optimization goal and the geometric constraints that drive the mathematical
formulation of the optimization algorithm.
To access the
Goals and Constraints
PropertyManager:
- In a Topology study tree, right-click Goals and
Constraints, and select one of the three optimization goals:
Best Stiffness to Weight Ratio, Minimize
Mass, or Minimize Maximum
Displacement.
Select Goal
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Best Stiffness to Weight ratio
(default)
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The optimization algorithm yields the shape of a
components with the largest stiffness considering the given amount
of mass that will be removed from the initial maximum design
space.
When you select
Best Stiffness to Weight ratio, the
algorithm seeks to minimize the global compliance of the model which
is a measure of the overall flexibility (reciprocal of stiffness).
Compliance is defined by the sum of strain energies of all
elements.
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Minimize Maximum Displacement
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The optimization algorithm yields a shape that
minimizes the maximum displacement on a single node (calculated from
a static study). With a given percentage of material to remove from
a component, optimization yields the stiffest design that weighs
less than the initial design and minimizes the maximum observed
displacement. |
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Minimize Mass with Displacement
Constraint
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The optimization algorithm yields a shape that weighs less than
the maximum size model and does not violate the given target for
the displacement constraint. The algorithm seeks to reduce the
mass of a component while restricting the displacement (max
observed value of component or user-defined at a single node)
under a certain limit.
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Constraints
Constraints limit the design
space solutions by enforcing the percentage of mass that can be eliminated to be under a
certain value, or by setting performance targets for the maximum displacement observed
in your model. You can define up to two constraints for one optimization goal. The User
Interface filters the type of constraints you can apply based on the goal you
select.
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Mass constraint
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Set the targeted mass that the
part will be reduced by during optimization. Select one of the following:
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Reduce mass by
(percentage)
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Type the targeted percentage of mass
reduction
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Reduce mass by (absolute
value)
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Type the exact value of the mass to
remove from the part's maximum design space.
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The optimization algorithm will attempt to reach the targeted
mass reduction for the final shape through an iterative
process. |
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Displacement constraint
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Sets the upper limit for the
selected displacement component. In
Component, select the desired displacement
variable. Select one of the following:
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Specified
value
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Type the targeted value for the selected
displacement variable, and set the desired units in
Units.
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Specified factor
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Type a factor to multiply the maximum
displacement calculated from a static study.
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Select one of the following for a reference vertex location for
the displacement constraint:
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Automatic (single max point)
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The program selects by default the vertex of the maximum
displacement observed in the model.
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User defined
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Select in the graphics area the reference vertex for the
displacement constraint.
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