Case study with and without assigning property
Objective :
To import the given 0000.rad file in hyperworks with the RADIOSS interface and to run the file with and without applying recommended property parameters to get the output files and then find the differences in the simulation run on absence and presence of property parameters
Procedure - CASE 1 : ( Base Simulation )
- Import 0000.rad file in the RADIOSS interface of hyperworks
- To change the run time to 55ms , select the cards tab in browser window and select ENG_RUN in which set the Tstop value as 55
- And to change the animation steps during simulation which could be calculated in terms of frequency
Frequency = Termination Time / Animation frames
In our case the Termination time is 55 and Animation frames is 25 , thus 55/25 = 2.2
To assign these value , select Cards tab in browser window and select ENG_ANIM_DT in which set the Tfreq value as 2.2 - To run the base simulation no parameters are to be assigned in the property
- After which to RUN the simulation , go to Analysis panel in main menu and select RADIOSS , check all parameters and select input file location
CLICK RADIOSS to RUN - The simulation Runs and the files are generated in the mentioned location
- Go to the files generated and open 0001.out file to view the energy error and mass error
- Energy error to very maximum level of +5% is acceptable model , -5% represents a good model and better to be close to 0%
At ideal conditions -15% - After which plot rigid wall forces using Hyperview
- Select Hyperview icon from the Toolbar and in load model select the h3d file from the files generated from RUN for the animation
- Since all the animation files are consolidated in h3d file
- Using page window layout , split the window for convenienece
- To view Graph /Time history output , select hypergraph icon in the toolbar
- Load the datafiles for representing graphs
- The T01 files are selected that are generated during RUN
- In hypergraph window, paramters to fill are Y type , Y request , Y component
- First select -
Global variables in Y type
Internal energy , kinetic energy , hourglass energy , Total Translational Energy in Y request
MAG in Y component - The graph with all the input data are plotted
- Then select -
Rigid wall/R-wall in Y type
4 Rigid wall 1 in Y request
Resultant NF , Resultant TF , total resultant force in Y component - Next open the Hyperview window and select contour icon in the toolbar
- In Result type select Displacement or Von mises as per requirement of study
- And the Run and its analysis of the input given, is done using hyperworks without input of property parameters
Procedure - CASE 2 : ( Recommended property Simulation )
- Import 0000.rad file in the RADIOSS interface of hyperworks
- To change the run time to 55ms , select the cards tab in browser window and select ENG_RUN in which set the Tstop value as 55
- And to change the animation steps during simulation which could be calculated in terms of frequency
Frequency = Termination Time / Animation frames
In our case the Termination time is 55 and Animation frames is 25 , thus 55/25 = 2.2
To assign these value , select Cards tab in browser window and select ENG_ANIM_DT in which set the Tfreq value as 2.2 - To run the simulation , all the recommended parameters are to be assigned in the properties
Such as Ishell , Ismstr , Ish3n , N , Ithick , Iplas - After which to RUN the simulation , go to Analysis panel in main menu and select RADIOSS , check all parameters and select input file location
CLICK RADIOSS to RUN - The simulation Runs and the files are generated in the mentioned location
- Go to the files generated and open 0001.out file to view the energy error and mass error
- After which plot rigid wall forces using Hyperview
- Select Hyperview icon from the Toolbar and in load model select the h3d file from the files generated from RUN for the animation
- Since all the animation files are consolidated in h3d file
- To view Graph /Time history output , select hypergraph icon in the toolbar
- Load the datafiles for representing graphs
- The T01 files are selected that are generated during RUN
- In hypergraph window, paramters to fill are Y type , Y request , Y component
- First select -
Global variables in Y type
Internal energy , kinetic energy , hourglass energy , Total Translational Energy in Y request
MAG in Y component - The graph with all the input data are plotted
- Then select -
Rigid wall/R-wall in Y type
4 Rigid wall 1 in Y request
Resultant NF , Resultant TF , total resultant force in Y component - Next open the Hyperview window and select contour icon in the toolbar
- In Result type select Displacement or Von mises as per requirement of study
- Use legend option to edit , where limits could be edited to represent the indicators. Thus this helps to filter and indicate the values that requires attention
- Use measures option in the toolbar to view the maximum and minimum value of stress and its location
- And the Run and its analysis of the input given , is done using hyperworks with input of property parameters
Result and conclusion :
- 0000.rad file imported and simulation run performed with and without assigning property parameters
- After running the simulation the 0001.out files in both the cases gives the energy and mass error
- These seems to be differing like in the first case the energy error is getting reduced to very least value of -10%
- Whereas in the second case the energy level is maintained or stays close to 0% and it is at -0.1% - shows stability
- In Hypergraph , after plotting the energies and forces in both case 1 and case 2
Case 1 : explanation
* Since in the beginning , when the beam starts crushing with the rigid surface , huge force with mass & velocity developed
* So kinetic energy and resultant NF is high initially
* Slowly the impact of force with the wall reduces and deformation starts
* Due to this deformation the initial force experienced by the rigid surface gets reduced
* Which in turn force is experienced by the beam
* Where due to this internal energy increases and kinectic energy decreases with time
* Frictional force varies accordingly with the deformation
* There is no change in TTE - Total Translational Energy
* Hourglass energy increases with deformation and time is seen
Case 2 : explanation
* In case 2 with recommended property applied there are some changes
* The kinetic energy as similar to case 1 initially is high and slowly drops
* And kinetic energy at a point drops slightly higher than case 1
* Simialrly the internal energy increases gradually and boosts slightly higher than case 1
* There is no change in case of TTE - Total Translational Energy
* In case of Hourglass energy it is NIL - This shows better result is case 2 ( By assigning recommended properties ) - In Contour plot , just to observe the variation in dimension and deformation , both the cases where observed in the same FRAMES 15
- There are changes between case 1 and case 2
- Thus by applying the recommended parameters there could be much better control over Hourglass formations
Hourglass :
These are cases when during deformation , the component undergoes strain and stress with changes in dimension and causing deformation of elements and nodes
During these times when Nodes are moved due to stress but if not been recorded this is known to be zero energy and callled hourglass energy
There are methods to control hour glass
* Either it could be control by physical stabilization
* Method known as perturbation
* Viscous and Stiffness are two ways to control hourglass
* In which Viscous are better in solving after hourglass has occured
* But stiffness are better in solving before hourglass arises
* To assign better and to solve hourglass issue as per recommendation Ishell = 24 ( QEPH )