optiSLang - ANSYS Workbench Interface (optiPlug)

A brief introduction

Dipl.-Ing. (FH) Andreas Veiz

Benefits of optiPlug

• Export your Project directly from ANSYS Workbench• Easy selection of the input and output parameters –

just „click and go“• Pre-defined problem files and start script• Possibility to import selected designs to verify the results

Selecting your cad parameters• Load your CAD geometry (e.g. in ANSYS Design Modeler)

• Highlight the desired parameters with a „D“ to add them to theparameter manager.

• You can change the parameter values now easily

Verifying the parameters

• Verify the values of the selected parameters• Verify the correct allocation of the parameter names to the values

Values

Allocation

• You have selected your geometry parameters of the CAD model.

• Now start a new Workbench simulation

• Define the analysis

Selecting your parameters in Workbench

• Highlight the desired output parameters with a „P“ to add them to the parameter manager

Overview input and output parameters• Open the ANSYS Workbench Parameter Manager• You have now an overview of your inputs and outputs• Make sure that every desired parameter is selected properly• Save the simulation and the project before using the interface

Using the optiPlug interface

• Click on the optiPlug – write button to start the plug in

Settings of the interface• Define the working directory for optiSLang• Define the project name• Set your default parameter range• Select whether the project should be stochastic oder optimization• Click on Start to export your project now

Directory

Project name

Problem type

Parameter range

Importing your project in optiSLang• Close the Workbench simulation and project• Open optiSLang• Import the pre-defined project

• Start the project manager

• Select „Import“

• Browse for the project

• Select theproject file(*.fgpr)

Parametrize the problem• Start the modification of the pre-defined parameters

Modifying the parametrization• Fill in the correct bounds for the analysis (ovierview on sheet 13)

Overview: upper and lower bounds

Parameter name value range

Flanschbreite_E6_1_DS 50 45-150Rohrstaerke_E6_2_DS 20 1-50Einflusstiefe_E6_3_DS 150 140-250Einflusstiefe2_E6_4_DS 150 140-250Flanschstaerke_E6_5_DS 20 10-30Flanschstaerke2_E6_6_DS 20 10-30Verrundungsbreite_E6_7_DS 10 5-20Verrundungsbreite2_E6_8_DS 10 5-20Schraubendurchmesser_E13_9_DS 12 6-24Schraubenspalt_E13_10_DS 2 0.1-3Schraubenkopfueberstand_E13_11_DS 10 2-10Schraubenlage_E13_12_DS 100 65-250Schraubenkopfstaerke_EX29_13_DS 12 4-24Schraubenkopfstaerke_EX32_14_DS 12 4-24

Defining the dependent parameters• Remove Verrundungsradius_E6_15_DS and

Verrundungsradius2_E6_16_DS from the parameter tree• Mark the value and define a new dependent parameter.• Insert „Verrundungsbreite_E6_7_DS*sqrt(2)“ for Verrundungsradius

and „Verrundungsbreite2_E6_8_DS*sqrt(2)“ for Verrundungsradius2

Creating input constraints• Due to the geometry it is necessary to define four input

constraints that limit the variation space of the parameters corresponding to the different geometries

• Define the four constraints in the constraint section

Creating input constraintsThe input constraints:1. Flanschbreite_min (minimum of the flange width)0 <= Flanschbreite_E6_1_DS-Schraubendurchmesser_E13_9_DS-

2*Schraubenkopfueberstand_E13_11_DS-fmax(Verrundungsbreite_E6_7_DS,Verrundungsbreite2_E6_8_DS)-1-1

2. Schraubenlage_min (minimum of the bearing of the screw)0 <= Schraubenlage_E13_12_DS-Schraubendurchmesser_E13_9_DS/2-

Schraubenkopfueberstand_E13_11_DS-fmax(Verrundungsbreite_E6_7_DS,Verrundungsbreite2_E6_8_DS)-Rohrstaerke_E6_2_DS-50-1

3. Schraubenlage_max (maximum of the bearing of the screw)0 <= Rohrstaerke_E6_2_DS+Flanschbreite_E6_1_DS-

Schraubenlage_E13_12_DS-Schraubendurchmesser_E13_9_DS/2-Schraubenkopfueberstand_E13_11_DS+50-1

4. Schraubenspalt_max (maximum of the gap of the screw)0 <= Schraubenkopfueberstand_E13_11_DS-

Schraubenspalt_E13_10_DS-0.2

Starting the Design of Experiments• Save and exit the parametrization• Start the Design of Experiments flow. You see that the starting

script and the problem file is already selected it is pre defined by the plug in• Choose Latin Hypercube Sampling and insert a Sample Size of 450.

Because of the input constraints will be about 110 samples be valid.• Chose the valid sample

points by deleting the invalid (click on Delete)

• Click OK and startthe DoE to solve thedesigns

Result and Postprocessing I

• See that we have bad results in two areas• 1st: the displacement of Flansch 1 cannot be negative• We have to remove these bad designs

Deactivating unsuitable designs I• Draw a window around the

designs you want to deactivate• Deactivate them by mark them

as deactivate (context menu byclicking the right mouse button)

• See the reduced design space

Deactivating unsuitable designs II• Watch for other areas of bad results• Repeat deactivating Designs in

these cases. You find the other area of bad designs when you lookat the equivalent stress.

• Save your modified result file to start a new postprocessing.

Postprocessing the reduced bin file• Take the reduced model to search for dominating parameters of

the desired target values.• The target values for the optimization are:

- Equivalent stress in the screw- Displacement of Flansch 1 and 2

Coefficients of determination

• Look at the Coefficients of determination of the target values.

• Check for double Parameters to reduce the model.

• Dominating Parameter:Rohrstaerke_E6_2_DS

Reducing the model

• You can reduce the parameters to 6 parameters by ignoring the parameters with a weak influence.

• The remaining parameters are:• Rohrstaerke_E6_2_DS• Schraubenlage_E13_12_DS• Schraubenkopfstaerke_EX_32_14• Einflusstiefe_E6_3• Einflusstiefe2_E6_4• Schraubendurchmesser_E13_9_DS

• Now you can reduce the parameter set in a new parametrization!• Be aware, that you have to modifiy the geometry constraints in

an accurate way!

Modifying the problem file• Set the unnecessary parameters as „inactive“

• Check the constraints, modify them as shown below:• Constraint 1: 18-Schraubendurchmesser_E13_9_DS• Constraint 2: 0 <= Schraubenlage_E13_12_DS-

Schraubendurchmesser_E13_9_DS/2-Rohrstaerke_E6_2_DS-71• Constraint 3: 0 <= Rohrstaerke_E6_2_DS-

Schraubenlage_E13_12_DS-Schraubendurchmesser_E13_9_DS/2+89

• Constraint 4: remove

Adding the objective function

• Start the parametrization again and add the objective function• Our aim is to minimize the displacement of the two flanges and

minimize the equivalent stress in the screw • Insert the objective as shown below• fabs(value) provides the absolute value

Starting an optimization• Because of the input constraints you can only use the GA or EA

algorithm for the optimization.• Define the optimization run. This is not pre-defined, so that you

have to fill in the correct problem definition and starting script.• Set 0% to avoid the violation of input constraints.• Modify the settings for the population size (25) and the mutation

rate (0.2) as shown below and start the solver.

Result monitoring and postprocessing• Best Design in this run is design Nr. 177• Reducing of the maximum equivalent stress by about 66%• The Gap could not be reduced yet

Comparing of the designs

• Basic Design:Displacement: 0.054867 mmMax. Stress in Screw: 55.239 MPa

• Optimized Design:Displacement: 0.072812Max. Stress in Screw: 18.5926 MPa

Import a design in Workbench• Re-open the Workbench Simulation• Browse for the design you want to import• Highlight „Calculate this design“ if you want to check the results

Calculated, imported design• See the changed parameters and results