OptiStruct is a proven, modern structural solver with comprehensive, accurate and scalable solutions for linear and nonlinear
analyses across statics and dynamics, vibrations, acoustics, fatigue, heat transfer, and multiphysics disciplines.
The OptiStruct Example Guide is a collection of solved examples for various solution sequences and optimization types and provides
you with examples of the real-world applications and capabilities of OptiStruct.
This section presents nonlinear small displacement analysis examples generated using OptiStruct. Each example uses a problem description, execution procedures, and results to demonstrate how OptiStruct is used.
This section presents nonlinear large displacement analysis examples generated using OptiStruct. Each example uses a problem description, execution procedures, and results to demonstrate how OptiStruct is used.
This section presents nonlinear transient analysis examples generated using OptiStruct. Each example uses a problem description, execution procedures, and results to demonstrate how OptiStruct is used.
This section presents normal modes analysis examples generated using OptiStruct. Each example uses a problem description, execution procedures, and results to demonstrate how OptiStruct is used.
This section presents complex eigenvalue analysis examples generated using OptiStruct. Each example uses a problem description, execution procedures, and results to demonstrate how OptiStruct is used.
This section presents thermal and heat transfer analysis examples generated using OptiStruct. Each example uses a problem description, execution procedures, and results to demonstrate how OptiStruct is used.
This section presents analysis technique examples generated using OptiStruct. Each example uses a problem description, execution procedures, and results to demonstrate how OptiStruct is used.
This section presents shape optimization example problems, solved using OptiStruct. Each example uses a problem description, execution procedures and results to demonstrate how OptiStruct is used in shape optimization.
The examples in this section demonstrate how topography optimization generates both bead reinforcements in stamped
plate structures and rib reinforcements for solid structures.
A tube made of two sheet metal pieces is intended to carry a load in both bending and torsion. The cross-section of
the tube may be of any shape, but due to manufacturing requirements, it must remain constant through the entire length.
A rectangular thin-walled box is to be used to store fluid. The outward bulging of the sides of the container (due
to the pressure of the contents) is to be minimized. Additionally, the maximum outward displacement of the side panels
must be below a given value.
This example involves a rectangular, thin-walled container used for storing fluid. The objective is to minimize the
outward bulging of the sides of the container caused by the pressure of its contents. Additionally, the maximum outward
displacement of the side panels must be below a given value.
Finding a good reinforcement pattern for a single modal frequency is difficult when dealing with beaded plates since
adding stiffness in one direction often reduces stiffness in another direction.
Topography optimization has applications beyond creating beads in shell surfaces. Since the basic topography approach
can be applied to any model containing large fields of shape variables, it lends itself to solid model applications,
as well.
Pattern grouping lends itself very well to applications where manufacturing conditions must be met. In this example,
topography optimization is used to form a design concept out of a solid block. Manufacturing the design concept using
a casting method is preferable.
The examples in this section demonstrate how the Equivalent Static Load Method (ESLM) can be used for the optimization
of flexible bodies in multibody systems.
This section presents multiphysic examples generated using OptiStruct. Each example uses a problem description, execution procedures, and results to demonstrate how OptiStruct is used.
This section presents response spectrum examples generated using OptiStruct. Each example uses a problem description, execution procedures, and results to demonstrate how OptiStruct is used.
This section presents nonlinear explicit analysis examples generated using OptiStruct. Each example uses a problem description, execution procedures, and results to demonstrate how OptiStruct is used.
The OptiStruct Example Guide is a collection of solved examples for various solution sequences and optimization types and provides
you with examples of the real-world applications and capabilities of OptiStruct.
The examples in this section demonstrate how topography optimization generates both bead reinforcements in stamped
plate structures and rib reinforcements for solid structures.
A specific part of the structure is to be loaded in torsion (Figure 1).
The part is to be formed using a stamping process.
Only the shape of the plate can be changed, the thickness cannot be
changed.
Topography optimization divides the design region into smaller areas, each with its
own shape variable. OptiStruct performs this process
using the parameters defined by the user. The design space consists of the entire
plate minus the areas near the loads and constraints. The smaller areas can each
move upward. The inner portions of these smaller areas are shown fully deflected in
Figure 2.
The potential reinforcement pattern can be any combination of these variables
deflected at any height between zero and the user-defined maximum height. OptiStruct creates a reinforcement pattern of any shape by
manipulating the 174 discrete shape variables. The pattern could resemble an X, an
oval, a series of straight beads, or any number of the millions of potential
designs. By setting various parameters, you can ensure that any design OptiStruct creates is manufacturable.
Once OptiStruct generates the shape variables, it begins
the optimization of the plate. The objective in this example is simple, the
stiffness of the plate under the given torsion load is to be maximized. OptiStruct performs a series of analysis runs to evaluate the
stiffness of the plate, determines what variable value changes will improve the
stiffness of the plate, and applies those changes to the model. After much
iteration, OptiStruct reaches the maximum design at a
point where the stiffness can no longer be improved. The solution is shown in Figure 3 where the colors display the heights of the bead reinforcement patterns. A finite
element model based on that solution is shown in Figure 4. The symmetry of the solution is due to the use of an OptiStruct design symmetry plane feature.
The face of the plate is covered with X-shaped cross-beads that work well in torsion.
None of the beads run completely across the plate in a straight line which would
reduce their effectiveness. Finite element analysis of the plate revealed a well
distributed stress pattern and low deflection at the load point.
The traditional method is to design a reinforcement pattern in the form of raised
"beads" across the surface of the plate, test the stiffness of the plate, and
increase the stiffness of the plate until it meets the design requirements. The
efficiency of the plate in terms of cost and weight is strongly dependent upon how
good the reinforcement pattern is, so it is critical to generate a good one. Two
examples of conventional bead reinforcement patterns for the plate in twisting model
are shown in Figure 5. These patterns are ones which would commonly be found in commercial
products.
Results
The plate generated by OptiStruct using topography
optimization is far stiffer than both of the conventional plates shown in Figure 5. Peak deflection for the topography plate is 0.83mm. For the conventional plates,
the peak deflections are 1.27mm for the one on the left and 6.47mm for the one on
the right. The plate developed with OptiStruct is 35%
stiffer than a good conventional design and far better than a poor one. The poor
design, while following the conventional wisdom of using an X-shaped reinforcement
pattern, uses beads that run completely across the plate in a straight line which
are susceptible to kinking when loaded. Such design mistakes are caught and
corrected by OptiStruct during the optimization process
allowing it to yield a superior design.