Spot Weld Simulation_sanitized

8/8/2019 Spot Weld Simulation_sanitized

1/28

Spot Weld Simulation

WB 13

Nov 1, 2010

tpp


2/28

Investigation

Develop a small example model built in WB

DM and WB Mechanical

Demonstrate two approaches to representingspot welds for the example model

1. Spot welds modeled by the point feature in DM

2. Spot welds modeled by line bodies in DM

Compare results for the two approaches and

highlight their advantages and disadvantages


3/28

Approach 1:

Spot Welds By Point Feature Use the point feature in DM to model spot welds

which become beam spiders behind the scenes inMechanical

Advantages Useful automations available for constructing spot

welds in the geometry

Disadvantages

Beam spiders are not visible or accessible

Mesh is typically irregular due to imprinted points inthe welded bodies

Results tend to be stiff and irregular


4/28

Point Feature Spot Welds

Point feature generates spot welds that imprint

vertices in the faces of the guide bodies


5/28

Surface Bodies Only

Geometry in Mechanical does not include any

representation of the spot welds


6/28

Spot Weld Connections

Spot welds are represented by vertex pair

connections


7/28

Mesh with Spot Weld Connections

Imprinted vertices cause the mesh to

be irregular


8/28

Boundary Conditions


9/28

Deformation

Unsymmetric result due to irregular mesh

and beam spiders


10/28

Stress

Irregular stress result


11/28

Element Nodal Forces

Forces due to hidden beam

spiders representing spot welds


12/28

Vibration Mode 1


13/28

Vibration Mode 2


14/28

Vibration Mode 6


15/28

Approach 2:

Spot Welds By Line Bodies and Contacts

Use the point feature in DM to create locations for vertices of linebodies that will represent the spot welds in Mechanical with MPCbonded contact, but ignore bodies with the imprinted vertices

Advantages

Line bodies are accessible in Mechanical to set cross section size andmaterial properties

Mesh for welded bodies is not imprinted with vertices, mesh istypically more regular then when vertices are imprinted

Results are more regular and less stiff than with beam spiders

Results for line bodies that represent the spot welds are available

Disadvantages Line body construction is currently more manual

Contacts have to be generated manually, there is currently noautomations available


16/28

Line Bodies from Points to Represent

Spot Welds

Point are not imprinted into

surface bodies

Can set the cross

section size


17/28

Line Bodies Representing Spot Welds

Can set the material


18/28

MPC Bonded Contact Connections


19/28

Mesh with Line Bodies and Contacts


20/28

Boundary Conditions


21/28

Deformation

Symmetric and smooth result


22/28

Stress



23/28

Element Nodal Forces



24/28

Element Nodal Forces on Line Bodies

Forces are available for the accessible and visible

line bodies that represent the spot welds


25/28

Vibration Mode 1


26/28

Vibration Mode 2


27/28

Vibration Mode 6

Smooth result


28/28

Summary

Two approaches to modeling spot welds have beeninvestigated, advantages and disadvantages of each havebeen listed

The approach that uses line bodies and MPC contact is

arguably superior Enhancement recommendations for WB DM and WB

Mechanical

Generate line bodies in DM by automations similar to the pointfeature that is current available for spot welds modeling withoutimprinting vertices in the faces of guide bodies

Options to automatically generate connections in Mechanicalbetween vertices and faces to bond vertices of line bodies tofaces of welded bodies

Spot Weld Simulation_sanitized

Documents

Transcript of Spot Weld Simulation_sanitized