Assignment 2-RADIOSS Engine File Editing & 3D Meshing Challenge

RADIOSS Engine File Editing & 3D Meshing

Objective:-

• To calculate speed of sound through steel and critical timestep for the given length.
• To edit engine file with critical timestep and the frequency at which output plots are generated (20 steps).
• To 3D mesh housing assembly with the given criteria.
• To 3D mesh arm bracket with the given criteria.

Questions:

1. Check the material properties of the rail component and calculate the speed of sound in steel rail=_______

• Import the FIRST_RUN_0000.rad file using File>solver deck>File- FIRST_RUN_0000.rad>import

• Now go to model tree>material>steel

• Another way of checking the material properties is by opening the FIRST_RUN_0000.rad file in notepad.

Here the Unit system used is g-mm-ms

Young’s Modulus E=210000 N/mm2

Density = 0.0078 mm3

Poissons ratio= 0.29

Speed of sound c=`√E/ρ` =`√210000/0.0078` = 5188.74 mm/ms

2. The length of the rail is about 1000 mm. Calculate the time takes for a shock wave to travel from one end of the rail to the other.

Length of the rail =1000 mm

Time taken by shockwave = (length of rail)/ (speed of sound) = 1000/5188.74 = 0.1927 ms

3. Time for sound to travel length of rail T_s = 1927 ms

4.Edit the engine file so that the stress wave can be monitored, moving from one end of the rail to the other during impact -this will require a termination time equal to the time it takes for the sound to travel the length of the rail(set on/RUN card)

• Import the FIRST_RUN_0000.rad file using File>solver deck>File- FIRST_RUN_0000.rad>import

• Now change the Tstop value from 60 to 0.1927 by Model tree>Cards>ENG_RUN

• Now change the T_freq value from 1 to 0.009635 by Model tree>Cards>ENG_ANIM_DT

• Now go to Analysis>Radioss

We have to select a location to save the file and then click on Radioss

• After the earlier step a window will pop up and tell that output has been generated.

5. Set the frequency of animation output to a time that will give 20 animation steps (/ANIM/DT)

Time related to frequency of animation T_freq = T_s/ (Animation steps) = 0.1927/20 = 0.009635

• Now change the T_freq value from 1 to 0.009635 by Model tree>Cards>ENG_ANIM_DT

• Another way to change the value is to open FIRST_RUN_0001.rad in notepad

• Now we see in the folder where FIRST_RUN_0000.rad file is saved that there are 20 animation files.

6. Change /print -10.

• Change the N_print value to 10 by Model tree>Cards>ENG_PRINT

• To verify that the change/ print value is 10 open the FIRST_RUN_0001.out and see that difference between each consecutive cycle is 10

7. 3d meshing tetra mesh and hex mesh

• Repeat class examples and, maintain the quality.
• Target tet size=5mm,hex size=10mm,tet collapse=0.15.

HOUSING:-

MODEL:-

Procedure:-

• Import the model using File>solver deck>import

• Put the given elemental criteria in Preference>criteria file edit.

• Now let’s apply 2D tria mesh on the hub using (2D>automesh) and hide the cover

• Check the quality criteria of the 2D mesh using Tool>Check elems

• To 3D mesh the hub go to 3D>tetramesh.

First we have to give the parameters in 3D>tetramesh> tetramesh parameters

Now go to 3D>tetramesh>Tetra mesh and mesh the hub

• Now check whether the 3D elements are formed or not go to (Tools>Mask) and mask some elements

• Now we have to volume tetra mesh the cover to do that go to 3D>tetremesh>Volume tetra

• Now check whether the 3D elements are formed or not go to (Tools>Mask) and mask some elements

• Let’s check the quality criteria of the 3D mesh go to Tools> Check elems> tet collapse

ARM BRACKET:-

MODEL:-

Procedure:-

• Import the model using File>solver deck>import

• Put the given elemental criteria in Preference>criteria file edit.

• Now we to do 2D mesh of the base using 2D>automesh and make sure there are no tria elements.

• Before 3D mesh lets measure the height of the base using Geom>distance>two points

• Now to do 3D mesh go to 3D>elems offset>solid layers

• Now we have to mask all the hex8 elements of the base using (Tools>mask>elems(by config-hex8)>mask) and unhide the arm_curve

• Now to 3D mesh the arm_curve go to (3D>Spin>spin elems>spin-)

• But before that we need centre of the curve to get that go to (Geom>Distance>three nodes>circle center). Select any three nodes on the curve for N1, N2 and N3 and the click on circle center.

• Now go back to (3D>Spin>spin elems>spin-) and select the elements shown in the picture and select curve center as the base node.

• Now we need to generate faces of the arm_curve to do that go to Tools>faces>arm_curve>find faces

• Now we have to 2D mesh of front face of the arm_straight using (2D>automesh) and make sure the no. of elements matches correctly with the front face of the arm_curve.
• Now to 3D mesh this go to (3D>linear solid) for ‘from’ the elements of the arm_curve are selected and for ‘to’ the elements of the arm_straight are selected and sure the node orientation matches correctly.

• Now we delete the faces (Tools>faces>delete face)

• Now we have to 2D mesh the boss face (2D>automesh)

• Now we have to 3D mesh the boss using (3D>line drag>general>mesh).Select the opposite face of boss as destination surface and select correctly the node path and line for along vector option.

• Now delete all the quad elements using (Delete>elems(by config-quad 4)>delete)

Conclusion:- The project was completed successfully.