Geometry cleanup for a Electronic Enclosure and creating the workflow in Ansys workbench

Objective:

The power-based assembly was provided for the challenge. And we need to create a workflow in the Ansys workbench and also import the CAD model into Spaceclaim.

Introduction:

ANSYS Workbench combines access to ANSYS applications with utilities that manage the production workflow.

Applications that can be accessed from workbench include

• ANSYS DesignModeler (for geometry creation).
• ANSYS Meshing (for mesh generation).
• ANSYS FLUENT or ANSYS CFX (for setting up and solving fluid dynamics analyses).
• ANSYS CFD-Post (for postprocessing the results).

In Workbench, a project is composed of a group of systems. The project is driven by a schematic workflow that manages the connections between the systems. From the schematic, you can interact with workspaces that are native to the workbench, such as Design Exploration (parameters and design points), and you can launch applications that are data-integrated with workbench (such as ANSYS FLUENT or ANSYS CFX). Data-integrated applications have separate interfaces, but their data is part of the workbench project and is automatically saved and shared with other applications as needed. This makes the process of creating and running a CFD simulation more streamlined and efficient.

Workbench allows you to construct projects composed of multiple dependent systems that can be updated sequentially based on a workflow defined by the project schematic. For instance, you can construct a project using two connected fluent -based systems where the two systems share the same geometry and mesh and the second system uses data from the first system as its initial solution data. When you have two systems connected in this way, you can modify the shared geometry once and then update the results for both systems with a single mouse click without having to open the meshing application or fluent. Some examples of when this is useful include: performing a reacting flow analysis starting from the solution obtained from a cold flow analysis; performing a second-order analysis starting from the solution obtained from a first-order analysis; and performing a transient simulation starting from the solution obtained from a steady-state analysis

Also, Workbench allows you to copy systems to efficiently perform and compare multiple similar analyses. Workbench also provides parametric modeling capabilities in conjunction with optimization techniques to allow you to efficiently investigate the effects of input parameters on selected output parameters

• Ansys space claim ist the new CAD cleanup tool for all Ansys products.
• Geometry simplification repair and modification is significantly streamlined compared to Ansys design modeler.
• At version-18, several of the \"Design modeler Electronic Utility\" capabilities have been incorporated into ANSYS Space claim.

1. Use space claim commands to defeature the enclosure

SpaceClaim:

It is a solid modeling CAD (Computer-aided design) software that runs on Micro-soft windows and developed by SpaceClaim Corporation.

SpaceClaim Corporation was founded in 2005 to develop 3D solid modeling software for mechanical engineering. Its first CAD application was launched in 2007 and used an approach to solid modeling where design concepts are created by pulling, moving, filling, combining, and reusing 3D shapes. It was acquired by Ansys in May 2014, Inc, and was integrated into subsequent versions of Ansys Simulation packages as a built-in 3D modeler.

SpaceClaim Corporation markets SpaceClaim Engineer directly to end-user and indirectly by other channels. SpaceClaim also licenses its software for OEMs, such as ANSYS, Flow International Corporation, CatalCAD, and Ignite Technology.

Process for the setup the simulation :

First, we need to import the geometry into the Space claim and we need to remove the wanted objects from the geometry and close the openings which are unwanted in the geometry outer cabinet of the power-based assembly objects.

After removing the unwanted geometry projections that are not necessary for the simulation, we need to close all openings that are required for the geometry and we need to remove the chamfers and the radius of the cabinet of the power supply system.

Split Body tool:

Use the Split Body tool to split a body by one or more of its faces or edges. Then select one or more regions for deletion. The Split Body tool expects that you have already selected the cutter objects. From these faces or edges, the single target body is inferred, since a face or edge can only belong to one body or surface. If only one body face is selected as a cutter, the default action is to extend that face to cut as far as it can through the body. If the face of a surface is selected, then it is automatically removed.

The Split Body tool works in two modes:

• \"Slow mode\" is activated by clicking a Split Body tool guide. In this mode, once a tool guide is clicked, it remains selected until another tool guide is clicked. This mode works just like any other tool.
• \"Fast mode\" automatically activates tool guides and moves you through the workflow. This predictive model allows you to box-select multiple cutters to add even more efficiency.

You can use the Split Body tool to:

• Split a body by its edges
• Split a body by its faces
• Split a body by a plane

You can select a body or surface from the Structure tree as the target and a plane from the Structure tree as the cutter.

When splitting with a plane passing through the entire body, some cuts may not be desired. Use the Local Slicing option to gain specific control over which cuts are applied.

To split a body by one of its faces

• Click the Split Body tool from the Intersect ribbon group.
• Select the faces or edges you want to use to cut the body.
• Hold Ctrl and click or draw a box to select multiple faces or edges.
• You can create temporary geometry and select it to cut the body.
• Mouse over the body to see the regions created by the cut.

To selectively split a body:

1. Click the Split Body tool in the Intersect group on the Design tab
2. Select the body
3. Check ON the Local Slicing option
4. Click the cutter plane; you will see a blue outline which previews local slicing locations for splitting the body
5. Click on a blue outline preview to cut the body; the Select Regions tool guide is then activated, however, holding the Ctrl key or clicking the Select Cuts tool guide allows you to create additional cuts
6. Click a region to delete it.

After the total clean up of the outer cabinet of the power supply geometry, we will end up with the geometry as shown above.

2. Use Icepack commands to convert CAD shapes into Icepak primitive shapes.

The term geometric primitive, or prim, in computer graphics and CAD systems is used in various senses, with the common meaning of the simplest (i.e. \'atomic\' or irreducible) geometric objects that the system can handle (draw, store). Sometimes the subroutines that draw the corresponding objects are called \"geometric primitives\" as well. The most \"primitive\" primitives are point and straight line segments, which was all that early vector graphics systems had.

In constructive solid geometry, primitives are simple geometric shapes such as a cube, cylinder, sphere, cone, pyramid.

Modern 2D computer graphics systems may operate with primitives which are lines (segments of straight lines, circles, and more complicated curves), as well as shapes (boxes, arbitrary polygons, circles).

The icepak enhancements Icepak simplification levels in Space-claim.

Level-0:

It converts geometry to a bounding box prism

Level-1:

It converts geometry to a collection of prisms

Level-2:

It converts geometry to a polygonal approximation

Level-3:

It keeps the geometry as it is(use only when needed)

All other graphic elements are built up from these primitives. In three dimensions, triangles or polygons positioned in three-dimensional space can be used as primitives to model more complex 3D forms. In some cases, curves may be considered primitives in other cases, curves are complex forms created from many straight, primitive shapes.

Identification of the Icepak objects:

Auto identify simple Icepak shapes in space claim

after the initial geometry cleanup, we completed the identity objects command-tab automatically create simple icepak shapes

A common set of two-dimensional primitives includes lines, points, and polygons, although some people prefer to consider triangles primitives because every polygon can be constructed from triangles.

The images below show the cad objects that are needed to be converted into the icepak bodies using the Icepak primitive shapes.

The Icepak primitive shapes are been used to convert the CAD shapes into Icepak bodies and after converting the shapes into icepak bodies will end up with the following geometry as shown

After converting the total bodies into the icepak bodies we will end up with the geometry as shown below.

At last in the space claim, we will end with the geometry as shown in the image below.

3. Save converted geometry:

After converting the geometry into the icepak format then the geometry must be saved as the required file of the icepak format

The image below shows how the files must be saved regarding the icepak format. The file must be saved with a save as type of Icepak Project(*.icepakmodel).

After saving the icepak file we will end with the following files as shown in the figure. The Ansys workbench creates a bunch of files that contains the module file for the Icepak geometry.

Directory structure:

1. dpn:

This is the design point directory. This essentially is the state of all parameters for a particular analysis. In the case of a single analysis, there will be only on \"dp0\" directory.

2. dpall:

It contains subdirectories \"global\" for mechanical analysis.

3. Session_files:

It contains the journal files of the current workbench project.

4. User_files:

It contains output files(images, animations), input files, user macro files, etc. that may be associated with a project.

If we open the icepak file then we will able to see the geometry file of the icepak module in the icepak folder.

The model file is the geometry that has been saved in the icepak folder.

4. Open saved converted model into Icepak

After we open the saved geometry in the icepak module then we able to see the model tree listed as shown below in the image.

If we expanded the geometry model tree then we will end up with the geometry which has all open and which has total icepak bodies in the geometry as shown below.

After that we open the icepak and the converted model will be imported we can see a lot of objects and we have managed all the components and I have imported all components of the geometry.

Always see that the total components have been imported into the icepak module otherwise it may affect the simulation process, also give an error in the meshing process for the geometry elements.

5. Check the geometry in Ice-pak

After we open the saved geometry in the icepak module then we able to see the model tree listed as shown below in the image.

Cabinet:

The cabinet is the enclosure that contains most of the components of a power supply need.

Opening for the power supply enclosure:

The specific openings are provided on all sides of the cabinet and we need to check whether the openings are been created correctly in the icepak after importing them.

Final geometry in the icepak.

The final geometry that contains all components and the fin elements on the baseboard must correctly be verified in the model tree after import geometry into the icepak.

The solid model of the geometry has been shown above.

6. Modify components in Ice-pak to define the correct physics.

We should also check all intersection object that is been self-intersecting that should be taken care of before doing meshing for the geometry and also applying the correct physics for the icepak domain objects.

The error shown above is an intersection of the object that has been self-intersecting the domain element.

We can modify components into two types such as assemblies and groups.

example:

we can collectively select all the similar elements in the geometry and make them into a group. Such as grouping all capacitors in a single unit and group name as the capacitors.

Conclusion:

we have successfully created a workflow for the icepak module using the Ansys workbench and converted the CAD objects into the icepak bodies using the primitive shapes provided in the space claim and imported the geometry into the icepak module.