ansys optislang - dynardo gmbh...optimization hook ansys aim 1. define geometry_mass as objective 2....

1

Tutorial

ANSYS optiSLang Optimization of a Steel Hook in ANSYS AIM

2

Optimization ● Hook ● ANSYS AIM

Tutorial ANSYS optiSLang © Dynardo GmbH

Optimization of a Hook

• How to change the hook, such that

the v. Mises stress will not exceed 300MPa,

• the mass will be as minimal as possible and

• certain geometry parameters will be within

predefined bounds?

Software recommendations:

• ANSYS AIM 17.2 or higher

• ANSYS Workbench optiSLang

plugin 5.2 or higher

3



DS_Angle (120-150°) DS_Thickness (15-25 mm) DS_Depth (15-25 mm) DS_LowerRadius (45-55 mm)


Design parameters

4




Boundary conditions (in ANSYS AIM)

• F= 6000 N

• Fixed support

element size = 1.5mm

fixed support

Force F= 6000N

5




Responses (in ANSYS AIM)

• For the objective and constraint condition the stress and mass are parameterized:

6



Solver: ANSYS AIM

• Open the ready to use AIM project hook_AIM.wbpz

• Save the project in your project directory

1.

7



Solver: ANSYS AIM

1. Open “Home”, “Units” and change Units to “Metric (kg,mm,s,°C,mA,mV)”

1.

8



Sensitivity Analysis

1. Double-click on the sensitivity module to start a new sensitivity analysis

1. 1.

9



Definition of Input Parameters

2.

1. Set Parameter type “Optimization” for all parameters

2. Specify the ranges of the geometry parameters

3. Press “Next”

1.

10


1. Define Geometry_Mass as objective

2. Multiply Geometry_Mass with 1e6 in the Expression field

(scale objective and constraint to the same order of magnitude)

3. Define a maximum stress

of 300 MPa as a constraint

4. Press “Next”


Definition of Objectives and Constraints

1.

2.

3.

4.

11



Definition of Sampling Scheme

1. Keep the default Advanced Latin Hypercube Sampling (ALHS)

2. “Finish” the sensitivity wizard

1.

2.

12



Running the Sensitivity Analysis

1. Start the sensitivity analysis

using “Update”

2. Now, the DOE is created in

the background and all designs

are calculated

3. Finally, the MOP is generated

1.

13


Results of the Sensitivity Analysis

• The approximation quality is excellent for both output variables

• The influence of the angle and the lower radius is relatively small


14



Optimization using MOP

Link an optimization task to

the MOP box (Drag & Drop)

15




Alternative:

Transfer Data from MOP

to an Optimization Unit

16




• Parameters are linked automatically to the sensitivity system

• All parameters are automatically considered as non constant

• Press “Next”

17




1. “Import criteria” from the sensitivity system

2. Select “obj_Geomnetry_Mass” and “constr_Equivilent_Stress_max”,

press “OK”

3. Confirm criteria dialog with “Next”

1.

3.

2.

18




optiSLang helps you to find a suitable optimization algorithm. Support the

underlying (automatic) selection process with some additional information

about the solver and the problem itself.

1. Set the analysis status as “Preoptimized” (best design from Sensitivity)

2. Set the constraint violations to “Seldom”

3. Set failed designs to “None” (MOP gives always response values)

4. Set solver noise to “None” (MOP gives a smooth surface)

1.

2.

3.

4.

19




1. Suggested algorithm is NLPQL

2. Press “Finish”

1.

2.

20




1. Validation of the Best Design is default in the optimizer settings

2. Run the optimizer by using “Update” in the context menu

2.

1.

21




• The optimizer converges in a few iteration steps

• The responses and objective/constraints of the best design are verified

• Due to the global approximation the constraints of the best design may

be violated in the verification

Validate best design is very important for the optimization on the MOP

22



Optimization using Direct Solver Calls

1. Drag a new optimization on the DOE of the sensitivity system

1.

23



1. Parameters are linked automatically to the sensitivity system

2. All parameters are automatically considered as non constant

3. Press “Next”


24



1. Objectives and Constraints are linked automatically to the sensitivity

2. All Objectives and Constraints are automatically transferred

3. Press “Next”


2.

3.

25



1. Use default settings at additional information page

2. Use Suggested algorithm ARSM

3. Press “Finish”


2.

3.

1.

26



1. Run the optimizer

by using “Update”

in the context menu

1.


27



• The ARSM converges to the global optimum

• In the post-processing the approximated and verified values of the

responses, objectives and constraints are indicated


28



Visualize the Optimal Design

1. Open the Workbench Design Table

2. Select the optimal design from the last optimization run

3. Use “Copy inputs to Current” to set input parameters to geometry

4. Update Geometry and visualize the results in the ANSYS AIM Study

2.

3.

29



Visualize the Optimal Design

Optimal geometry Equivalent Stress

30



Initial vs. Optimal Design

Initial Design Optimal Design

Mass = 752g Mass = 612g

Equivalent Stress = 459,9 MPa Equivalent Stress = 299,9 MPa

31



If you have any questions belonging this tutorial do not hesitate to contact

[email protected]

phone +49 (0) 3643 9008-32

ansys optislang - dynardo gmbh...optimization hook ansys aim 1. define geometry_mass as objective 2....

Documents