Assignment 5
Objective: To mesh the component, check FE for quality, running the simulation with altering the bundary conditton, contact surface and making some structural changes
1. Open the .hm file in hypermesh and mesh the component from the 2D, Automesh panel, with the target element size of 6 unit
2. Quality check of the FE
Running the simulation
Step 1: Import the solver deck in Hypermesh from the import tab
Step 2: Once the import is complete, go to model browser and there you can change material,property, failure card, etc
Step 3: Once the necessary changes are made in the model browser, go to Analysis> Radioss
Select Export option : All
Run Option : Analysis
Run Number : 1
Options : -nt 8
Choose a specific folder to write simulation file there and hit radioss button, Solver window will open and will solve the problem
Case 1: Run the crash tube model as it is.
Sneaking into FAILURE_JOHNSON_0001.out file to view Energy and mass error
Energy Error : 3.8%
Mass Error : 0%
Number of Cycles : 83640
Ellapsed time : 108 s
Vonmises stresses animation
Displacement
Contact Energy vs Time
Internal Energy vs time
Rigid wall forces vs time
Combined plots
Results: From the animation it is observed that the bottom part from the notch was gone under deformation and then the rest of the part got deformed. The contact energy increased upto a point, the a decline was observed further ended with a flat curve. Internal energy increased and holds its maximum value till the last of the siulation. Contact Energy increased very slowly upto 30sec ad thereafter a surge was observed.
Case 2. Change the Inacti=6 and run
Sneaking into FAILURE_JOHNSON_0001.out file to view Energy and mass error
Energy Error : 3.8%
Mass Error : 0%
Number of Cycles : 83640
Ellapsed time : 107.48 s
Vonmises stresses animation
Displacement
Contact Energy vs Time
Internal Energy vs time
Rigid wall forces vs time
Combined plots
Results: From the animation it is observed that the bottom part from the notch was gone under deformation and then the rest of the part got deformed. The contact energy increased upto a point, the a decline was observed further ended with a flat curve. Internal energy increased and holds its maximum value till the last of the siulation. Contact Energy increased very slowly upto 30sec ad thereafter a surge was observed.
Case 3: Create the type 11 contact and run
Sneaking into FAILURE_JOHNSON_0001.out file to view Energy and mass error
Energy Error : 4%
Mass Error : 0%
Number of Cycles : 83755
Ellapsed time : 121.80 s
Vonmises stresses animation
Displacement
Contact Energy vs Time
Internal Energy vs time
Rigid wall forces vs time
Combined plots
Results: After the introduction of type 11 contacts, energy error was increased from 2.7% to 4% and the same goes for the ellapse time. No signifigant graph pattern change was observed, but heighest values of contact and internal energy was observed.
Case 4: Remove both notches and remove boundary condition on rigid body node then run
Sneaking into FAILURE_JOHNSON_0001.out file to view Energy and mass error
Energy Error : 2.7%
Mass Error : 0%
Number of Cycles : 75329
Ellapsed time : 110.73 s
Vonmises stresses animation
Displacement
Contact Energy vs Time
Internal Energy vs time
Rigid wall forces vs time
Combined plots
Result : Removing the notch and the boundary condition lower down the energy error to 2.7%, with minimum diplacement noted. minimum of contact energy and maximum vonmises and internal energy were observed.The graph patter does not show much variation from the previous simulations.
Case 5: Create a new notch in the middle ,select the whole section and run
Sneaking into FAILURE_JOHNSON_0001.out file to view Energy and mass error
Energy Error : 3.3%
Mass Error : 0%
Number of Cycles : 80821
Ellapsed time : 117.36 s
Vonmises stresses animation
Displacement
Contact Energy vs Time
Internal Energy vs time
Rigid wall forces vs time
Combined plots
Results: Butterfly pattern was observed in the animationin the lowerpart of the member structure, with maximum displacement and minimum R-Wall forces was observed.
Case 6: Create a new notch with nodes only from opposing 2 faces and run
Sneaking into FAILURE_JOHNSON_0001.out file to view Energy and mass error
Energy Error : 2.7%
Mass Error : 0%
Number of Cycles : 81193
Ellapsed time : 189.81 s
Vonmises stresses animation
Displacement
Contact Energy vs Time
Internal Energy vs time
Rigid wall forces vs time
Combined plots
Results : New notch were created on the opposite sides of the face, minimum energy error, maximum Eeapsed time minimum cycles and maximum R-Wall forces were observed.
Conclusion
- Component was meshed with shell elements, and quality check was done on FE
- Hypercrash was used to manupulate various crash parameters
- Simulation was performes
- Results were plotted in Hyperview
- Change in the internal energy was observed, it is found maximum in case of no notch FE and minimum in case of type 11 contact
- Effect of removing the notch notch
1. Von Mises stress increases
2. Internal Energy was observed to be maximum
3. Minimum Energy Error
4. Minimum Displacement was observed
5. Minimum Contact Energy was observed
| S.No | Point of Comparison | 1 | 2 | 3 | 4 | 5 | 6 |
| 1 | Energy Error | 3.8% | 3.8 | 4% | 2.7% | 3.3% | 2.7% |
| 2 | Mass Error | 0% | 0% | 0% | 0% | 0% | 0% |
| 3 | Elapsed Time | 108 s | 107.48 s | 121.80 s | 110.73 s | 117.36 s | 189.81 s |
| 4 | Total Number of Cylces | 83640 | 83640 | 83755 | 75329 | 80821 | 49356 |
| 5 | Max Displacement | 2.800E+02 | 2.800E+02 | 2.798E+02 | 2.790E+02 | 2.831E+02 | 2.803E+02 |
| 6 |
Vonmises, Min Max |
0 7.403E-1 |
0 7.403E-1 |
0 7.474E-01 |
0 8.194E-01 |
0 7.542E-01 |
0 7.612E-01 |
| 7 |
Internal Energy, Min Max |
0 4.227E+04 |
0 4.227E+04 |
0 4.218E+04 |
0 4.279E+04 |
0 4.254E+04 |
0 4.262E+04 |
| 8 |
Contact Energy, Min Max |
0 2.034E+03 |
0 2.034E+03 |
0 2.079E+03 |
0 1.381E+03 |
0 1.705E+03 |
0 1.595E+03 |
| 9 |
Resultant Normal Rigid wall forces Min Max |
0 1.340E+03 |
0 1.340E+03 |
0 1.359E+03 |
0 1.187E+03 |
0 1.178E+03 |
0 1.367E+03 |
| 10 |
Outcome Points |
Maximum Cycles Minimum Vonmises |
Minimum Elapsed time Maximum Cycles Minimum Vonmises |
Maximum Energy Error Minimum Internal Energy Maximum Contact Energy |
Minimum Energy Error Minimum Displacement Maximum Vonmises Maximum Internal Energy Minimum Contact Energy |
Maximum Displacement Minimum R-Wall Forces |
Minimum Energy Error Maximum Elapsed time Minimum Cycles Maximum R-Wall Forces |