The mixable-density method is an expanded re-implementation of the density-based method, aiming to deliver the same capabilities as well as additions to these capabilities.
Furthermore, this development was motivated by the need to:
Unify and to mutualize some components between all the optimization methods.
Better align and streamline the density-method within the overall structural optimization framework.
Gain consistency between all the optimization methods.
As a result, the mixable-density method:
Delivers smoother results based on a new numerical scheme.
Incorporates the benefits of other methods and conversely (cross fertilization process).
Can be combined with other methods in an optimization problem enabling you to manage complex systems with dedicated requirements.
Review the following requirements and limitations associated with performing a mixable density-based optimization analysis. These limitations apply only to the optimization analysis and are not applicable to any downstream design validation systems. Go to a section topic:
Element Type Requirements
The density-based optimization analysis supports Solid elements in the optimization region. The application excludes any other element type used in this region from the optimization solution.
General Limitations
The mixable density-based optimization analysis method does not support:
Imported Plies (Composites).
Graphical view of Exclusions created by Direct FE boundary conditions.
Cracks defined within the Fracture object.
If you specify the Solver Type as , the application only supports Response constraints types of Mass and Volume and Manufacturing Constraints where only the Minimum Member Size can be specified.
Use of Section Planes with Topology Density and Topology Elemental Density results. Note that the User Defined Result does support this feature.
Pre-stressed Modal analysis.
Large-deflection effects in a Static Structural analysis (NLGEOM, ON).
Nonlinear contacts (supported contact includes and ).
Axisymmetric model when you wish to define a Global Stress Constraint and Local von-Mises Stress Constraint.
Any Thermal system linked to the upstream Static Structural system.
A solution run on high performance computing (HPC) using Distributed Ansys across multiple machines, when:
You have Thermal Condition included in a Static Structural analysis linked to a Structural Optimization analysis.
You want to optimize a Static Structural analysis that is linked to an upstream Steady-State Thermal analysis.
A Structural Optimization that includes a Reaction Force Constraint.
Modal Analysis Limitations
When linked to a Modal analysis, the mixable density-based optimization analysis does not support:
Damping when the Damped property set to (and therefore also the Campbell Diagram chart).
solver selection.
Linked Static Structural Analysis Limitations
When linked to a Static Structural analysis, the mixable density-based optimization analysis does not support the following boundary conditions:
Fluid Solid Interface.
EM Transducer.