Surface wrap of Power train Components using ANSA

OBJECTIVE 

       The objective of this project is to surface wrap the parts of the powertrain and delete the geometry and compress the file. Then combine the parts by importing it in one common file and convert them into a single volume entity by creating a seamless connection.

Surface Wrapping 

        It is an act of replicating an external or an internal surface details on to a negligibly thin surface. It is an advanced form of surface meshing which is used to mesh a model, with the increasing complexity of working geometry only the meshing & analysis time is more. In external or internal CFD flow analysis only the surface which is in contact with the fluid is considered. So reduced the computation and meshing time we prefer this technique.

PROCEDURE

        Import the engine file first into the ANSA and delete the parts which are used for creating the model.

                                                      TOPO mode of the Engine part

The unchecked faces are checked using the untrim tool from the surfaces, the function creates a new Face that extends over the whole of the surface of a selected Face. This eliminates the uncheck face error.

Wrap --> Elements -  Constant length wrap is a very fast algorithm that can create a watertight triangular surface mesh of uniform size from an assembly of unconnected and intersecting components. It can be used for various analyses like CFD, NVH and more.

Release --> Elements - Function releases the shell or solid elements, which have been generated on macro-areas, from the underlying geometry or volume respectively. The node and element ID's remain intact.

Fill hole --> Cons - Function fills holes on faces and the holes can be of any shape. Such internal openings can be selected individually, or automatically among the visible ones if they fall below a user-specified diameter value. There is the option to create automatically 3D curves, points or connection points of the removed holes, in order to mark their shape and position for reference.

Since external flow analysis is performed the holes may cause distortion in the wrap so the holes are covered and then wrap option is used.

The target element size for the engine component is 8 & for the other parts is 5.

                                                           Wrap model of Engine 

Transmission

       Unchecked model of Transmission                              Wrap model of Transmission

Gearbox     

              Unchecked model of Gearbox                                         Wrap model of Gearbox

Merge --> file - Function activates the file manager in order to merge ANSA files or neutral format files to the currently loaded file in ANSA.

               Merge parameters dialog box

                                                 Assemble of the Power train

The merge option is used to import the different parts into a single file, then create a separate part and provide the names for the parts.

Merge parts create three-volume entities, convert them into a single volume entity for the flow analysis. Since wrap option converts all the cons into bounds all the tools under topo mode cannot be used.

Delete --> Elements - Function deletes selected shell or solid elements, feature area option is selected and the angle is set at 10 degrees and the interface surface is selected and deleted.

Click on the Open Foam option in the top right to create a boundary around the interface surface.

Release --> Function releases a number of selected grid points that belong to more than one FE-model entities. The edges option is selected and a close surface is created. Now delete the interface surface.

Different methods to join the gaps at the intersection surface.

Paste --> Grids - Function is used to paste nodes. The parameters to handle the pasting procedure are defined in the paste window that appears as the function is activated. Two selection modes are available (nodes and node sets). The user may define if the nodes will be pasted in pairs or to the last selected one. Moreover, the final position that a pair of pasted nodes will be placed, can be defined parametrically (0 -1). Note that the paste procedure affects the element's nodes and not the nodes themselves.

New --> Elements - function defines new elements by selecting nodes, edges, shell elements or facets.

Fill --> Shell mesh - Function serves to fill openings on the shell mesh. The gap will be closed with FE that will be created between two sequences of edges or perimeters. By selecting at least one more edges line or perimeter which connects the two opposite ones the resulted mesh will be connected also to those edges.

Swap --> Elements - Function rotates the shell edge picked by the user, inside the two shells which have that edge as common.

                     Before Swap                                                          After Swap

Reconstruct --> Shell mesh - Function is a powerful tool for the creation of a high-quality surface mesh. It examines a given mesh and performs re-meshing to correct problematic areas and optimize the overall quality of the mesh according to the mesh parameters. For Geometry mesh (macro-areas) all modifications are made on the underlying CAD surface.

               Before Reconstruct                                                      After Reconstruct

MV Surf --> Grids - Function moves a selected mesh node on the macro area's surface or a perimeter node along the perimeter segment on which it lies. Also, it moves a node belonging to the FE-model mesh on the surface which is defined by the adjacent shell elements.

                     Before MV surf                                                     After MV surf

The intersection of the Gearbox and Transmission 

The intersection of Engine and Transmission

The Complete model of the Powertrain

                            The Seamless connection is formed at the intersection surface

The different surface errors for the model are checked and the previous project procedure is used to correct it.

 https://projects.skill-lync.com/projects/Perform-Surface-Mesh-on-BMW-M6-model-by-clearing-the-Topological-errors-Create-wind-tunnel-25115

CONCLUSION

1. Surface wrap for the different parts like Engine, Transmission, Gearbox is successfully created and the element length of these parts is provided.

2. Three models were merged using the Merge option and a seamless model is created.