Example 9: Topology Design with Radial Extrusion Fabrication Constraints

Use the model rim_01.prt for this example.

Description

This example demonstrates how to use topology optimization to design a light and stiff structure.

Highlighted features

Min Strain Energy, Mass Fraction constraint, Radial Spoke (extrusion) fabrication constraint

Optimization problem statement

The following optimization problem will be created and solved:

• Objective:

◦ Minimize Strain Energy

With minimizing strain energy as an objective, it is to get the stiffest structure under the given load for the allowable amount of material.

• Subject to:

◦ Mass fraction <= 0.3

Analysis

The example contains one analysis. The loads/constraints are shown in the image below:

Mesh control

Maximum element size: 12 mm

Topology region

• References:

The component, excluding volume region 1, 2, and 3, as shown in the image below.

• Init. mass fraction: 0.2

When mass fraction is used as a constraint, it is recommended to use the same constraint bound value as the initial mass fraction value.

• Fabrication constraints:

◦ Radial Spokes about the Y axis of coordinate system WCS, Number of radial candidates = 120

◦ Cyclic symmetry about the Y axis of coordinate system WCS, Number of cyclic sections = 5

◦ Mirror symmetry about the XZ plane of coordinate system WCS

◦ Minimum member size: 24mm

It is recommended to set the Minimum member size to at least twice that of the mesh element size.

◦ Spread fraction: 0.5

Design objective

Minimize Strain Energy

Design constraints

Mass fraction <= 0.3

Optimization study

The study refers to the defined topology region, design objectives, and constraints

Advanced settings:

• For analysis output files, only the first and last cycle are requested.

• Use default settings for all other analysis and design parameters.

Topology Result

• Topology density isosurface

• Topology element density

Geometry Reconstruction

• Tessellated model

• Solid model