Assignment 3

Questions:

Comparison of results with base simulation and improved shell element properties

1.Using the crash beam file from the previous assignment, change the run time to 55 ms.

Answer :-

2. Change the number of animation steps during simulation to a minimum of 25 and maximum of 60.

Answer :-

3. Run the base simulation without any modification to element properties.

Answer :-

Import Solver Deck > Import

Analysis > options (-nt 4 ) > Radioss

It will generate Solution, and click the Result...

give the path for local modal and click Apply.

Click the Contour for simulation.

Internal Energy - MAG

4. At the end of the simulation, do the energy error and mass error checks and determine whether results would be acceptable.

Answer :- After getting energy and mass error, also the result's are acceptable.

Job completed

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

(a) Rigid Wall Force :-

(b) Internal Energy :-

(c) Hourglass :-

(d) Contact Energy :-

(e) Total Energy :-

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

Answer :-

Recommended properties :-

Parameters		Comment
Ishell =24		QEPH 4 nodes shells are best combination of cost and accuracy.
Ismstr=2		Full geometric nonlinearities (default)with possible small strain formulation activation in RADIOSS Engine.
Ish3n=2		Standard 3 noded shell (C0)with modification for large rotation(default)
N=5		Number of integration points set to 5 for accuracy bending.
Ithick=1		Thickness change is taken into account for accuracy.
Iplas=1		Iterative plasticity for good accuracy.

7. Follow steps 5 and 6.

Properties :-

Properties used before :-

New Property used :-

(a) Rigid Wall Force :-

(b) Internal Energy :-

(c) Hourglass :-

(d) Contact Energy :-

(e) Total Energy :-

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

SR.No.	Cases	Old Properties	New Properties
1.	Rigid Wall Force	3.500e+02	8.579e+02
2.	Internal Energy	7.0e+07	2.850e+04
3.	Hourglass	1.660e+04	0.000
4.	Contact Energy	3.500e+02	7.756e+02
5.	Total Energy	2.068e+01	6.287e-01

9. Comment whether there is any change in the results and why there is any change in the result.

Answer :-

As we can see in Q8; both old & new Properties result's are mentioned with their different cases. Both cases are having different values as per their different properties & their comparission are mentioned below :-

1 Rigid Wall force :- old prop. value < new prop. value

2. Internal Energy :- old prop. value > new prop. value

3. Hourglass Energy :- old prop. value > new prop. value

4.Contact Energy :- old prop. value < new prop. value

5. Total Energy :- old prop. value < new prop. value

So, as per given input we got result as per the HM software output.