Project 2

                                                    PROJECT -2 {REAR SUSPENSION MODEL}

AIM: In this project 2, ANSA preprocessor  is used to generate mid surface, volume mesh. The quality criteria for some parts are different  . therefore, one should apply them while meshing clear all off  elements on surface mesh and then proceed to volume mesh . understand about various connection used in rear suspension and deploy them accordingly.

PROCEDURE:

STEP1: Import the geometry into ANSA and do topo to switch the surfaces, isolate each part and set PIDS for the rear suspension geometry

STEP2: Clean the geometry using checks manager. enable unchecked faces, collapsed cons, needle face, overlapped faces, cracks, single cons. Clear all issues until no error is found .

STEP3: One can do mesh generation for tyre and rim either by meshing them manually using spot mesh or by batch mesh .

• The  advantage of batch mesh is that ANSA will do topological clean up automatically which is a time saving process. even though sometimes we must clear some error manually after batch meshing.

VOLUME MESH GENERATION FROM TYRE AND RIM

• After  clearing all the off elements on the surface mesh one can proceed further to volume mesh generation.
• Volume mesh can be created in ANSA only if it recongnizes the geometry as aclosed volume therefore, we must manually update our model to closed volume.
• To covert our model to closed volume one must define volume
• Ansa might crash if you generate volume mesh for the whole  geometry. so, define individual closed volume for diffferent PIDS.
• define volumes can be checked under list option under volume dialog box.

STEP4: I have used casting option for generation of mid surface for subframe and macpherson struct outer surface.

• The advantage of using casting is that ANSA generates mesh along with the mid surface.

STEP5: Surface mesh generation and volume mesh generation for remaning all parts , I have generated batch mesh by rotaing each part indivitually

• After generating batch mesh clear off element manually. Trias or ortho-trias are used as surface mesh for volume generated parts.

STEP6: After completion of mid surface and volume mesh we must connect them by using connections like bolt connection, spot weld connection etc.

• Bolt connection can be generated using RB2 option is nastran deck.

CLUSTER : This connection is used when a manual bolt connection must be deployed between two or more surface.

• For automatic bolt connection one must follow three steps , create COG is basically a 3D point, convert this 3D point to bolt a new open connection manager and select the bolt symbol which has created earlier step a then assign P1,P2,P3  select FE type as bolt and give the requised values and constraint apply and then realize the connection.
• I have simply given bolt connections by connecting two cluster RB2'S with two node RB2.

SPOT WELD: It is generally a solid connection deployed between 2 surfaces.

• For generating spot weld connection first create a COG point on the FE and now convert this 3D COG point into spot weld using convert option.
• Then select the generated spot weld point using connection manager. In the connection manager assign p1 and p2 for mid-surface which are to be connected using spot weld.

STEP7: TRANSFORM

• After completing surface mesh, volume mesh , mid surfacing and connection we have to use transform option in order to create exact mirror of the model on the other side.
• Use transform and select all the entities including connections to generate exact replica of the model on the other side.
• now, use symmetry a mirror 3 point plane option and select 3 point on the edge. these 3 point plane option and select 3 point on the edge. these 3 point represent all the 3 coordinate (x,y,z). this helps all the entities to transform on the other side.

CONCLUSION:

In this project , I  have generated mid surface and volume  mesh using different option available in ANSA. Did topological clean up  able to achieve better mesh flow using smooth reconstruct, swap, paste ,move ,option eliminated kinks and raised edges . successfully applied different quality criteria and mesh parameter for different part and cleared off element during mesh generation . successfully deployed connections for the rear suspension.Overall I have done preprocessing for rear suspension using ANSA.