Assignment 5-RADIOSS Interfaces & Study of Effect of Notches Challenge

AIM -To mesh the given bumper model with mesh size of 6 mm.

    To run the crash tube simulation with given 6 cases and plot the graph for energies.

1. Case 1:

We have to run the simulation as it is with no changes. Open Hypermesh with user profile as Radioss. To import the 0000.rad file, click on File > Import > Solver deck and import the file.

In order to create the THPART we have to click on the output Blocks and create the TH PART , in entity id instead of nodes keep components and select all four components and click on ok. Then the TH part is created.

From output file energy error is -3.8%%

Open hyperview to view animation and contour plots from H3d file

Open hypergraph 2d for observing the energy plot data from TA01 file.

discuss case 1 graph ----------------------------------

2. Case 2

In this case, the model is imported and run the simulation with recommended properties whereas we have to change Inacti = 6 as per problem statement. The Type 7 contact interface is used with recommended property as shown in the Figure 

After changing the parameters run the simulation with same steps to be carried as per previous case

discuss graph O/p -----------------

3.Case 3 

In this case, the model is imported and run the simulation with recommended properties whereas we have to change Card image as Type 11 contact as per problem statement.

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discuss graph --------------------------------

4 case 4

In this case, the notch needs to be deleted and make it into a plane mesh.

To delete the Notch, go to the Tools panel and select Delete option > Select the Elements to delete > Click on delete Entity.

The Notch elements are deleted.

To create a plane surface, go to the 2D panel, Select Ruled option > Select the first Node list > Select the Second Node List > Click Create. >> The mesh is created Give the element length as 6 > Click Recalculate > Click mesh.

The mesh is created properly. 

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radios run file 

 

Now to delete the Boundary conditions, go to the Solver Deck, If the Solver deck is not visible, Go to the View tab in the Standard menu bar > Click Browse > Click Hyper Mesh > Click on Solver > The Solver Deck will be opened. > Delete the BCS Entity in the Solver Deck.

discuss graph details ------------------------

5. Case 5

In this case, the model is imported and run the simulation with recommended properties where there is Notch presented on the middle surface and also the boundary conditions are removed.

Radios run File 

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To simulate the model, go to the Analysis Panel, Select the Radioss Option > Select the area to save the file (Note: Save the File in separate folder naming Case 5 as it will be easy to check the models) > Check include collectors box > In the options tab, type “-nt 4” > Click Radioss. The Simulation is run successfully.

6. Case 6

in this case, a notch should be created at the same place in the opposite direction.

in order to cfreate the notch go to - 2d - offset ele - offset the selected ele to create the notch 

Radios run file

To simulate the model, go to the Analysis Panel, Select the Radioss Option > Select the area to save the file (Note: Save the File in separate folder naming Case 6 as it will be easy to check the models) > Check includes collectors box > In the options tab, type “-nt 4” > Click Radioss. The Simulation is run successfully.

Result

                                             Energy Error (%)  Mass Error (%) Max. Contact force (N) Max. Rigid wall force (N)  Max. Contact energy (KJ)    

Case1   Running model as it is                -3.8              0                   69.53                   1400                              2                Node to Surface Contact Type 7  

Case2  Change Inacti = 6                      -4.8              0                   69.53                   1500                              2.6          No Initial Penetrations found

Case3  Type 11 Interface                      -3.9              0                   112.5                   1300                              1.9               Ty 11 Edge to edge contact 

Case4  Removing notches and BC’s         -2.5              0                 61.09                   1200                              1.3             no Bondary cond flat surface 

Case5  Creating new notch to middle         -3.6              0              61.94                  1300                               1.3         ability to absorb increased due to middle notch 

Case6  Creating notch only on opposite side     -3.2             0                   69.45                  1100                     1.5           due to Opposing notches

• -The change in the internal energy is due to the notch. With the removal of the notch, the internal energy decreases and hence reduces the energy error as well.
• -The notch areas have high stresses and deform first. In the plane surface where the notches are removed the stress levels are low. Hence, we can state that by removing the notch helps to reduce the stress acting in the body.

Conclusion :-  

.The Bumper model have been meshed and welded (seam) with the element size of 6mm and ready for further solving and post-processing.

.All the 6 cases of crash tube have been simulated and results are compared using various energies plot.