Week 9-Creation of 1D Connectors Challenge

AIM: To create various types of 1 D connectors.

Target Element size - 5 Units

S.N	Quality Criteria	Value
1	Aspect Ratio	5
2	Skewness	45
3	Warping	15
4	Taper	0.5
5	Min. Length	2 Units
6	Max. Length	8 Units
7	Min angle Quad	45
8	Max angle Quad	135
9	Min angle Tria	30
10	Max angle Tria	110
10	Tria %	15

Create connector and Attach the various parts of the given model

1. Right_Rail_2 & Front_truss_1:- Seam-Quad(angled+capped+L)
2. Left_Rail_2 & Front_truss_1:- Quad elements
3. Front_truss_2, Front_truss_1 & Right_Rail_1:- Spot weldwith 2 Layers and 5 mm Diameter
4. Front_truss_2, Front_truss_1 & Left_Rail_1:- Hexa (Adhesive)
5. Rear_truss_2 & Right_Rail_2:- Bolt Connector
6. Rear_truss_2 & Left_Rail_2:- Bolt Connector
7. Right_Rail_1 & Right_Rail_2:- Spot-weld with Rigid Elements
8. Left_Rail_1 & Left_Rail_2:- Spot-weld withSpring Elements
9. Rest all the component left Join them with suitable connector

CONNECTORS:

Connectors - connectors allow us to create relationships between two nodes in an FEA model when we discretize a complex CAD model. The connection can be simply made by using rigid or some of them will be weld or bolt connections, which can impose more complicated constraints

The reasons for using connectors are: connectors ensure the connectivity between parts in a model. To represent the geometric connection
in terms of FEA. And finally to transmit the force between the parts which are connected together.

In HYPERMESH:

In HyperMesh, connections can be created as a spot-weld, seam weld, adhesive, bolts, and masses. A realized connector will be considered as the successful representation of a CAD model in the preprocessing stage. Then it will be moved into the solver side. The input for the creation of the connector will be extracted from the CAD model or from the design data.

Types of connectors :

Seam Weld: The process of joining the workpiece which is made of similar or dissimilar materials along a continuous seam is known as seam weld.

Spot weld: It is a resistance welding process that is used primarily for welding two or more metal sheets together by applying pressure and heat to the weld area. Heat for the welding process will be obtained from resistance to electric current.

Bolt connector: It is a type of connection between structural members made with plates and bolts, as opposed to a riveted or welded construction. In HyperMesh it uses the RBE2 elements to create a bolt connection.

Adhesive: Adhesive connection is also used to connect two parts of the model. This works similar to how an adhesive would work in real life.

PROCEDURE:

Import the given model. And 2D mesh all the given surfaces as fine and keep all the parameters and quality criteria given above.

1.Right_rail_&Front_truss_1: Seam-Quad(angled+capped+L)

Select the Nodes from the edge of Right rail 2 from where we want the seam Quad with L section then select the two components also as we have some gap to fill increase the tolerance and spacing values.

2.Left_rail_2&front_truss­­_1: Quad elements

Similar to above select the nodes on edges but instead of seam quad select quad from type and create the quad weld but if the quad is in red then it is not realized so increase the tolerance or spacing value to make it realize.

3. Front_truss_2, Front_truss_1 & Right_Rail_1: Spot weldwith 2 Layers and 5 mm Diameter

Since this is a spot-type weld with a diameter of 5 and 2 layers, so first select nodes on front truss 2 and right rail 1 and use the spot weld option in connectors to join the two with the given diameter, similarly so for right rail 1 and from truss 2.

4. Front_truss_2, Front_truss_1 & Left_Rail_1:- Hexa (Adhesive)

As we did for seam type weld select the nodes on each component we need the adhesive to join them and select the components with tolerance to create the adhesive from seam type.

5. Rear_truss_2 & Right_Rail_2:- Bolt Connector

Use bolt type option for this but since there is no existing hole on the component we need to use the create hole if no option from the bolt property section and give the appropriate parameters to create it.

6. Rear_truss_2 & Left_Rail_2:- Bolt Connector

Similar to the above method same needs to be done here also

7. Right_Rail_1 & Right_Rail_2:- Spot-weld with Rigid Elements

For rigid elements, we need to select the spot type and select nodes along the edge of the right rail 1 component but since some of the nodes will be missed so select the option for finding the nearest nodes instead of projecting. Let the tolerance and diameter values remain the same.

8. Left_Rail_1 & Left_Rail_2:- Spot-weld withSpring Elements

Same as above needs to be done just instead of rigid type select the spring type.

For the remaining types, I used the following connectors,

1. a) seam quad(angle+capped+L) for Right rail 1 and Front Truss 2

RESULT:

CONCLUSION:

Researched all the types of connectors in hypermesh and successfully created the various connectors to joint the given components.