Challenge

Assignment 3

Objective : To Compare results with base simulation and improved shell element properties

Procedure:

1) Using the crash beam file from the previous assignment.

Import file in hypermesh through the import solver deck menu.
In the Model browser navigate Cards menu and click on the ENG_RUN (card image).
below in the ENG_RUN discription, in the "Tstop" sub panel change the run time to 55 ms from the previous value of 60 ms.

2) At the same sub panel in the 'Cards' panel,

Click on the ENG_ANIM_DT .
Change the number of animation steps during simulation by choosing it between a minimum of 25 and maximum of 60.
that is change value of 'Tstart' to 0 and 'Tfreq' to 1, as i choose animation steps to 55.

3) Running base simulation, without any further changes.

After the changes have done, go to the analysis tab in the bottom toolbar and click on radioss.
select export options to - all
select run options to - analysis
run number to - 1
select destination as the same folder where the basic 0000.rad file was located.
click radioss and after the simulation has been done, close that window and open the HyperView from the same menu to view the simulation.

4) Energy error and Mass error checks

5) Plot rigid wall forces, internal energy, hourglass energy, contact energy, total energy of the simulations.

6) Change all the shell elements properties to recommended properties, save this as separate, rad files and run the simulation.

Recommended properties:

7) Follow steps 5 and 6 for the parameters with new changed properties.

The changes done in the properties are shown below-

before - After -

The results for each required parameters at the end of simulation, for both the cases, are shown below:

Rigid wall forces -

before

after

Internal energy -

before

after

Hourglass energy -

before

after

Contact energy -

before

after

Total energy -

before

after

8) Create a brief report comparing all the results from steps 5 and 6 for both simulations.

displacement-

COMPARABLE FACTORS	WITH DEFAULT PROPERTIES (MAXIMUM AND MINIMUM )	WITH RECOMMENDED PROPERTIES (MAXIMUM / MINIMUM )
DISPLACEMENT	8.19E+02 AND 0.000E+00	8.411+02 and 0.000E+00
HOURGLASS ENERGY	9.46E+03 AND 000E+00	000E+00 and 0.000E+00
Voin mass YIELD CRITERIAN	349.9 mpa AND 000E+00	350 mpa and 0.000E+00
Internal energy -	1.95 x 10^7	1.95 x 10^7
Total energy -	6.1 x 10^7 AND 5.5 x 10^7	0.3E+05

Result:

A comparision report for the results between default and recommended shell properties has been made.
It is observed that the new shell elements gives a more precise and efficient method to analyse the simulation.

Conclusion:

Energy error is decreased to 0.1%
QEPH elements gave better results in case of loading and unloading
Hourglass energy stays same even after changing shell elements properties.
learned about the various shell element properties and it's effects on elements while simulation.

Ship work like this
in your own course.