Section 12 Assembly

Copyright © 2010 Altair Engineering, Inc. All rights reserved.Altair Proprietary and Confidential Information Assembly The bodies in an assembly interact with each other on the surface The interaction between the bodies can be classified into Cylindrical, Disc, Matching, Planar, and others Convert to Mesh body The CAD bodies are converted to Surface Mesh bodies The Surface Mesh bodies are then modified (assembled) to create matching nodes The modified surface mesh bodies may require local mesh cleanup Assembly module Has tools to generate mesh for CAD assemblies with matching nodes Align –Help align the mesh before creating matching nodes Join – Make the mesh congruent between the bodies

Copyright © 2010 Altair Engineering, Inc. All rights reserved.Altair Proprietary and Confidential Information In a cylinder, if one end of the cylinder is not proper, then we can extract a perfect cylinder from that face Extract Cylinder

Copyright © 2010 Altair Engineering, Inc. All rights reserved.Altair Proprietary and Confidential Information CAD models Need not be aligned properly Axis not collinear The radii of 2 mating cylinders is not the same (press fit) and so penetrate each other Overlapping faces can be inclined Can have features not required for analysis This tool is used to make the non conforming surface mesh bodies (non planar, non cylindrical faces or non circular, irregular edges) to conform Align

Copyright © 2010 Altair Engineering, Inc. All rights reserved.Altair Proprietary and Confidential Information Align

Copyright © 2010 Altair Engineering, Inc. All rights reserved.Altair Proprietary and Confidential Information Used for conforming non-planar faces. Before After Planar

Copyright © 2010 Altair Engineering, Inc. All rights reserved.Altair Proprietary and Confidential Information Used to reposition the nodes of the non-conforming cylindrical face to conform Before After Cylinder

Copyright © 2010 Altair Engineering, Inc. All rights reserved.Altair Proprietary and Confidential Information Used to reposition the nodes of the non-conforming circular edges to conform. Before After Circular

Copyright © 2010 Altair Engineering, Inc. All rights reserved.Altair Proprietary and Confidential Information Used to distribute the nodes of the circular edge uniformly along angular direction. Before After Radial

Copyright © 2010 Altair Engineering, Inc. All rights reserved.Altair Proprietary and Confidential Information Used to rotate bodies(bolts/valve seats) about some angle to match nodes. Before After Angular

Copyright © 2010 Altair Engineering, Inc. All rights reserved.Altair Proprietary and Confidential Information Surface mesh bodies with overlapping surfaces can be modified to have matching nodes by calling this function Two overlapping surfaces, each from 2 different bodies are selected for the Join operation After the Join process one or more surfaces are created that are common to the 2 bodies Shared Faces –Surfaces used by more than one body Shared Edges – Edges used by more than one body During the joining process, the surface mesh can become bad. Hence these faces are re-meshed This will make the mesh better without loosing the node congruency. The input to the Join can be bodies as well. In this case, the overlapping surfaces are automatically identified and the Join operation is called on each of the overlapping surface pairs Join

Copyright © 2010 Altair Engineering, Inc. All rights reserved.Altair Proprietary and Confidential Information Select the bodies and click Show. This will identify all the cylindrical faces between the bodies that are mating. The number of face pairs will be displayed. Click Join to assemble the bodies at these faces. Join – Cylindrical Face

Copyright © 2010 Altair Engineering, Inc. All rights reserved.Altair Proprietary and Confidential Information Common faces are identified. The number of elements in the axial direction can be controlled by entering the mesh size or number of divisions. Join – Cylindrical Face

Copyright © 2010 Altair Engineering, Inc. All rights reserved.Altair Proprietary and Confidential Information Align – Bodies (bolts/valve guides) can be selected for alignment to have good iso-mesh Preserve – Bodies whose cylinder radius has to be preserved can be input as preserve. Join - Align/Preserve

Copyright © 2010 Altair Engineering, Inc. All rights reserved.Altair Proprietary and Confidential Information The faces are joined and congruent nodes are obtained. Join - Align/Preserve

Copyright © 2010 Altair Engineering, Inc. All rights reserved.Altair Proprietary and Confidential Information This will identify the hollow disc faces that can be assembled. Join – Disc Faces

Copyright © 2010 Altair Engineering, Inc. All rights reserved.Altair Proprietary and Confidential Information Faces that are geometrically identical will be identified. (Shape) Face which are geometrically identical and whose node are at the same location (nodes lie on same location but not congruent) are identified. (Mesh) Join – Matching Faces

Copyright © 2010 Altair Engineering, Inc. All rights reserved.Altair Proprietary and Confidential Information All the planar mating faces will be assembled. Join – Planar Faces

Copyright © 2010 Altair Engineering, Inc. All rights reserved.Altair Proprietary and Confidential Information Partial cylinders are faces which are cylindrical in shape but not a complete one. For e.g half cylindrical faces will come under partial cylinder category. Join – Partial Cylinders

Copyright © 2010 Altair Engineering, Inc. All rights reserved.Altair Proprietary and Confidential Information Faces which do not fall under any of the above categorization will be identified as general faces. This will also identify the faces which fall under the above categorization but were not assembled. Join – General Faces

Copyright © 2010 Altair Engineering, Inc. All rights reserved.Altair Proprietary and Confidential Information This will show all the faces that are assembled and have shared faces. Shared Entities

Copyright © 2010 Altair Engineering, Inc. All rights reserved.Altair Proprietary and Confidential Information This is the reverse of Join Surfaces shared by multiple bodies will be replaced by surfaces that are not shared. But there will be coincident nodes at the locations of overlap. Separate

Copyright © 2010 Altair Engineering, Inc. All rights reserved.Altair Proprietary and Confidential Information Used to align the Hex meshed bolt with the bolt hole properly. Hex Bolt Align