ASSIGNMENT 3
ASSIGNMENT 3
- First i ran the simulation without modifying shell properties, and then opened the first_run_0001.out file in the notepad to check for energy and mass error checks.The energy error came out to be -10.3%, which was within limits , so i moved on to plotting the results for it.
Then i modified the shell element properties , and then ran the analysis , and there was a huge improvement in the energy errors as they were only -0.1% during the whole simulation.So i moved on to plotting the results.
- COMPARISON OF RESULTS
- THE ENERGY ERROR
--> There was a huge improvements in the overall results including the energy errors as it came down to only -0.1% in the improved shell properties analysis.
REASON : When the Ishell value was not specified , there was no consideration for the hourglass modes , but when Ishell value was set to 24(for QEPH), it took the hourgalss modes into consideration, but QEPH reduces the errors due hourgalss energy using the physical stabilisation methods by increasing the stiffness of the nodes at the material level , so reducing the hourglass effects before they even arise. Hence there was negligible energy error when Ishell value was set to 24.
2. RIGID WALL FORCES RESULTANT VS TIME PLOT
3. COMBINED PLOT - INTERNAL ENERGY, HOURGLASS ENERGY , KINETIC ENERGY, TOTAL TRANSLATIONAL ENERGY VS TIME PLOT
--> Here , it can be clearly seen that in the base simulation , there was considerable amount of hourglass energy , and no hourglass energy can be seen when the shell properties are improved. This is due to the above mentioned fact that Ishell value was set to 24.
4. CONTACT ENERGY VS TIME PLOT
-->The plots for contact energy are the same , as the change in shell properties doesnt effect the contact energy.
5. TIME STEP VS TIME PLOT
6. VON MISES CONTOUR PLOT
--> When the shell properties were improved , it can be clearly seen that the simulation has produced more realistic results in comparison to the base simulation in which the surface of the rail can be seen deforming and adjecent elements bending at the consecutive edge , which is unrealistic. The improved shell properties produce a surface that is deforming continuously with no kinks at the surface.