Simulating the model and compare the base simulation with the different kinematic conditions by using Hypermesh and Radioss

Object: Simulate the model and compare the base simulation with the different kinematic conditions.

Observation:

1. Plot RWALL forces, contact forces, internal energy and Create TH/PART for all parts and compare results for all cases.

2. How does the notch affect the results?

3.Plot energies and note any difference.

Procedure:

1. Creating the mesh for bumper assembly.

1. Run the crash tube model as it is without changing any parameters.

2. Change the Inacti=6 and run.

3. Create the type 11 contact and run.

4. Remove both notches and remove boundary conditions on a rigid body node then run.

5. Creating a new notch in the middle, select the whole section and run.

6. Create a new notch with nodes only from opposing 2 faces and run.

1. Creating the mesh for bumper assembly.

Creating the mesh for the bumper assembly with a mesh size of 6mm. Connect the elements by using the proper connectors.

1. Run the crash tube model as it is without changing any parameters.

Contact force polt.

Internal energy, Contact energy VS time.

Rigid wall force VS time.

Energy and mass errors:

Max contact force is 2.334E+1 N

Internal energy is 42000 J.

The number of cycles is 83600.

% error is -3.8 %.

Mass.err is 0.00.

2. Change the Inacti=6 and run.

 In this case, we are changing from the previous case Inacti=5 and run the model.

The below image shows changing the Inactive value.

Contact force polt:

Displacement plot:

Internal energy, Contact energy VS time.

Rigid wall force VS time.

Energy and mass errors:

Max contact force is 2.334E+1 N

Internal energy is 40000 J.

The number of cycles is 83600.

% error is -3.8 %.

Mass.err is 0.00.

3. Create the type 11 contact and run.

In this case, we are changing the type 7 contact to type 11 contact as shown in the below figure.

Contact force polt:

Displacement plot:

Internal energy, Contact energy VS time.

Rigid wall force VS time.

Energy and mass errors:

Max contact force is 1.004E+2 N

Internal energy is 43000 J.

The number of cycles is 83200.

% error is -3.8 %.

Mass.err is 0.00.

4. Remove both notches and remove boundary conditions on a rigid body node then run.

Contact force polt:

Displacement plot:

Internal energy, Contact energy VS time.

Rigid wall force VS time.

Energy and mass errors:

Max contact force is 5.63E+1 N

Internal energy is 45000 J.

The number of cycles is 78100.

% error is -3.0 %.

Mass.err is 0.00.

5. Creating a new notch in the middle, select the whole section and run.

Creating the new notch in the middle of the tube as shown below figure.

Contact force polt.

Displacement plot:

Internal energy, Contact energy VS time.

Rigid wall force VS time.

Energy and mass errors:

Max contact force is 1.842E+2 N

Internal energy is 41000 J.

The number of cycles is 96200.

% error is -3.6 %.

Mass.err is 0.00.

6. Create a new notch with nodes only from opposing 2 faces and run.

Contact force polt.

Displacement plot:

Internal energy, Contact energy VS time.

Rigid wall force VS time.

Energy and mass errors:

Max contact force is 1.9114E+1 N

Internal energy is 41500 J.

The number of cycles is 99900.

% error is -3.0%.

Mass.err is 0.00.

Conclusion:

1. The maximum contact force is decreasing there is no change in the internal and contact force.

2. Internal energy is increasing and time taken to run is decreasing.

3. The contact force is high in the case 6th as compared to all the cases.

4. After deleting the notches the simulation of the tube takes less time as compared to all the cases.

5. In the first case takes more time to simulate the model as compared to all the cases because it consists of more notches.