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CAD Editing Interface<\/h2>\n\n\n\n
The interface for CAD editing opens in the CAD context. If a user is editing simulations, then CAD editing interface disappears. The next Figure show the interface:<\/p>\n\n\n\n A user can modify a CAD which is assigned to a simulation and manually update the edited CAD in the simulation. Let’s show this workflow with an example.<\/p>\n\n\n\n A user assigned a CAD to a simulation:<\/p>\n\n\n\n Then the user realizes that the CAD has no flow volume, therefore the user creates a flow volume by clicking on the CAD in the GEOMETRIES tree and editing it.<\/p>\n\n\n\n Upon CAD modification, SimScale indicates, with the circular arrows, that the CAD in the simulation is outdated. SimScale does not automatically update the CAD in the simulation to the latest state. It must be done manually. When the user clicks on the CAD in the simulation, SimScale shows the CAD without the latest CAD modifications (the CAD is the same as the last time when the user edited simulation setup). <\/p>\n\n\n\n If the user would like to simulate the CAD without CAD modifications (without flow volume), then the user doesn’t need to do anything beside setting simulation and running it. The following operations are supported with more coming soon. The operations are categorized based on their application.<\/p>\n\n\n\n The Delete<\/em> operation helps you to delete a face from the CAD model by selecting ‘Delete’<\/strong> from the operations toolbar and then assigning one or multiple faces to be deleted. <\/p>\n\n\n The settings panel also allows choosing between the available healing methods, viz. Heal and cap while the face delete operation is being performed. Choose Leave Open to opt out.<\/p>\n\n\n\n In the following section, all the healing methods are described using simple geometry as follows:<\/p>\n\n\n The reference geometry is a cylinder with one of its edges rounded to produce 1 curved and 3 planar faces. <\/p>\n\n\n\n Heal<\/strong><\/p>\n\n\n\n The Heal<\/em> method will try to fill up the surface lost to the delete operation by trying to either expand or contract the adjacent faces until they intersect.<\/p>\n\n\n Cap<\/strong><\/p>\n\n\n\n The Cap <\/em>healing method will try to fill up the surface lost to the delete operation by connecting the adjacent faces without changing them.<\/p>\n\n\n Leave Open<\/strong><\/p>\n\n\n\n This healing method will leave a void as a result of the face delete operation and no additional efforts will be taken to heal the connecting faces.<\/p>\n\n\n With the Move <\/em>operation, you can move a face in the direction of its normal. Select ‘Move’ <\/strong>from the operations toolbar to open the settings panel for this operation. There are two methods to move faces. For illustration let’s consider the highlighted heat sink face:<\/p>\n\n\n First, select the face and then choose one of the following methods:<\/p>\n\n\n\n Distance<\/strong><\/p>\n\n\n\n Specify the distance up to which the selected faces need to be moved\/extruded.<\/p>\n\n\n Up to Entity<\/strong><\/p>\n\n\n\n Specify the entity face up to which the selected faces need to be moved.<\/p>\n\n\n <\/i>Important<\/p>\n <\/div>\n The move operation will fail if it causes intersections of the same body. In such case use the Extrude > Merge > Up to entity<\/em> option.<\/p>\n <\/div>\n<\/div>\n\n\n\n With the Extrude <\/em>operation, you can extrude a face in the direction of its normal by specifying the distance or the face of an entity up to which it should extrude. Select \u2018Extrude\u2019 <\/strong>from the operations toolbar to open the settings panel for this operation. There are three methods to extrude faces. For illustration let\u2019s consider the highlighted-blue face:<\/p>\n\n\n\n First, select the face and then choose one of the following methods:<\/p>\n\n\n\n Add New<\/strong><\/p>\n\n\n\n Add a new face to the existing one, while it is extruded in the normal direction. This operation creates an additional part.<\/p>\n\n\n <\/i>Did you know?<\/p>\n <\/div>\n Using a negative value in the Add new <\/em>type extrusion would result in the removal of a part of the geometry dividing it into two parts instead of adding a new part.<\/p>\n <\/div>\n<\/div>\n\n\n\n Merge<\/strong><\/p>\n\n\n\n Extrude the face, merging it with the previous one. Thus, the number of parts remains the same.<\/p>\n\n\n Remove<\/strong><\/p>\n\n\n\n Extrudes the face in the normal opposite direction, giving a removal operation.<\/p>\n\n\n <\/i>Important<\/p>\n <\/div>\n To perform extrude operation on multiple faces at the same time, ensure that all selected faces have the same normal.<\/p>\n <\/div>\n<\/div>\n\n\n\n Distance<\/strong><\/p>\n\n\n\n Specify the distance up to which the selected faces need to be extruded. All those Extruded operations in this section were made using the distance extrusion method.<\/p>\n\n\n Up to Entity<\/strong><\/p>\n\n\n\n Specify the entity face up to which the selected faces need to be extruded.<\/p>\n\n\n The Delete<\/em> operation will delete the solid bodies present in the CAD model. Click on ‘Delete’<\/strong> under Body<\/em> in the operations toolbar and assign one or more volumes from your CAD model before hitting ‘Apply’<\/strong>.<\/p>\n\n\n There are instances where the CAD is missing one or more faces (these CAD models are called sheet bodies) and you are unable to proceed in the simulation process. In such cases the Close Sheet <\/em>operation for bodies (volumes) is helpful. In the settings panel, select the bodies with missing faces to close and choose a closing method.<\/p>\n\n\n Closing Method<\/strong><\/p>\n\n\n\n The Closing method<\/em> defines how to close the sheet body using either the Cap<\/em> or the Grow <\/em>method. These methods are described below using an example of Crystal Towers:<\/p>\n\n\n The tower in the middle has a missing face on the top. Hence, the close sheet operation is perfect for this CAD model. <\/p>\n\n\n\n Cap<\/strong><\/p>\n\n\n\n The Cap<\/em> method looks for the minimum possible surface path to close the sheet body and is the default closing method. <\/p>\n\n\n Applying this method to the middle tower closes the top face with minimum possible surface area.<\/p>\n\n\n\n Grow<\/strong><\/p>\n\n\n\n The Grow<\/em> method will try to extend the connecting faces to the missing face until they meet at a vertex.<\/p>\n\n\n Applying this method by picking up the middle tower extends the connecting faces of the missing face elongating the middle tower until they all meet at a point. <\/p>\n\n\n\n Facet Split<\/em> allows users to split the CAD model into multiple faces based on the defined maximum split angle. This operation comes in handy when dealing with .stl files as they often consist of only a single face.<\/p>\n\n\n The angle can be added in degrees between 0 and 180 and is by default 30. <\/p>\n\n\n\n In order to detect interfaces between two solids or a solid and a fluid, we need to perform an imprint. This action cuts the interface between two bodies that are in physical contact into recognizable surfaces. Please refer to our article where a detailed explanation of what an imprint does<\/a> is well mentioned. <\/p>\n\n\n\n In the CAD mode, click on ‘Imprint’<\/strong>, then assign all the parts that need to be imprinted, and hit ‘Apply’<\/strong>.<\/p>\n\n\n In case the uploaded model does not match the original dimensions or the dimensions of your choice, the Scaling<\/em> operation can be used to adapt the model size accordingly. With scaling, the simulation setup parameters might also change and care should be taken to avoid unreliable results.<\/p>\n\n\n Assign all the bodies that need to be scaled. The settings panel also contains a slider to set a scaling factor while also allowing direct entry of the value.<\/p>\n\n\n\n The Split<\/em> operation allows users to cut individual CAD bodies into two parts based on the position and the orientation of the plane defined. <\/p>\n\n\n The orientation of the splitting plane is defined by specifying the normal to the plane. The part lying on the side where the normal vector points is retained, while the other part is removed. The user has the option to keep parts from both sides of the plane as well.<\/p>\n\n\n\n You might run into situations where your CAD model has multiple overlapping parts. This might pose a hindrance to the simulation physics causing the simulation setup to fail. If this is the case try our set of Boolean operations. These operations allow you to perform union, subtraction, and intersection operations between different parts. These are described below:<\/p>\n\n\n\n <\/i>Important<\/p>\n <\/div>\n To perform the boolean operations the user must select two or more bodies that share overlapping volumes.\r\nIf there are assigned bodies that don\u2019t overlap they will be excluded from the operation. Even if no parts overlap, the operation will still show as successful but no changes will be shown in the viewer and in the scene tree.<\/p>\n <\/div>\n<\/div>\n\n\n\n The Union<\/em> operation is used to merge two overlapping entities into a single entity. The resulting body encloses the volume of both overlapping entities. This is shown below:<\/p>\n\n\n<\/a>\n
Updating CAD in simulation<\/h2>\n\n\n\n
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If the user would like to simulate the CAD with CAD modifications (with flow volume), then the user clicks Update<\/strong> in the Geometry panel (which opens if we click on Geometry item in the simulation tree) and confirms the update (checkmark on top right). SimScale will then swap the CAD and provide feedback about the mapped entities in the simulation assignments.
<\/p>\n\n\n\nCAD Operations<\/h2>\n\n\n\n
Face<\/h2>\n\n\n\n
Delete face<\/h3>\n\n\n\n
<\/a><\/a><\/a><\/a><\/a>Move<\/h3>\n\n\n\n
<\/a><\/a><\/a>Extrude<\/h3>\n\n\n\n
<\/a><\/a><\/a><\/a><\/a><\/a>Body<\/h2>\n\n\n\n
Delete body<\/h3>\n\n\n\n
<\/a>Close Sheet<\/h3>\n\n\n\n
<\/a><\/a><\/a><\/a>Facet Split<\/h3>\n\n\n\n
<\/a>Imprint<\/h3>\n\n\n\n
<\/a>Scale<\/h3>\n\n\n\n
<\/a>Split<\/h3>\n\n\n\n
<\/a>Boolean<\/h3>\n\n\n\n
Union<\/h4>\n\n\n\n