Learning Forum

[sane0394]

Hie I am using Ansys 2021 version for the free-falling box on a fixed ground for this model I have designed my model in CATIA and imported it into the Ansys design workbench

• step-1 I have used boolean operation and united all bodies as one and ground as separated
• step-2 I have imported the aluminum alloy properties into the body
• step-3 meshing I have used the tetrahedral method with a 5mm body size

using this mesh size and aluminum properties I have applied courant -Friedrichs-Lewy (CFL) condition to get the time steps

E= 7.1*e^10

density (rho) = 2710

safety factor=1

delta t = 9.7*10^-7 I have considered as end time in Ansys

number of cycles = T/delta t = 2*10^6

• please enlight me if I used the correct steps to find the end time step and no of cycle in Ansys is wrong please tell me.

In my box design, I have used rivets as rivel for joining the sheet metals and in Ansys workbench, I haven't given any contacts between rivets and body to the ground as well by default Ansys have created the contacts

• if I have what type of contact do I have to use and what type of loads has to be given on rivets

• step-4 I have given the boundary condition like velocity and standard gravity to all bodies.
• step-5 I have given the rigid to the ground and fixed condition to it.
• step-6 I have run the simulation but my box was passing through the ground without causing an impact.

I have uploaded images, help me out where I have done wrong.

1.png

[Akshay Maniyar]

Instead of using this whole process, you can use the drop test wizard. So, there will be very less chance of any mistake. The Drop Test Wizard allows a fully automated setup of a drop test analysis within an Explicit Dynamics analysis. You need only supply a file containing the geometry of the object to be dropped in the analysis.
The wizard allows you to change the initial orientation of the geometry, and automatically creates a rigid, fixed target geometry within Mechanical which can also be oriented at an angle. The wizard applies impact velocity and standard earth gravity boundary conditions to the dropped geometry and defines contact behavior between the geometry and the target.
I have attached the Ansys help link for your reference.
Thanks Amaniyar

[sane0394]

thanks for your reply but I am unable to find the wizard can you guide me where it will.

[Akshay Maniyar]

The Drop Test Wizard must be first loaded into Mechanical, then opened using the icon in theEnvironmentContext tab.
After starting Workbench, selectExtensionsManage Extensions...
In theExtensions Managerwindow, select the check box next to MechanicalDropTest, then clickClose.
3. Add an Explicit Dynamics analysis system to the project. Click on Explicit dynamics and under environment tab you will find drop test wizard.

The Ansys help link I have shared in my last post has all the details about wizard for your reference.
Thanks Amaniyar

[sane0394]

I don't have an Ansys account to open the link.

[Akshay Maniyar]

Please check the following post on forum.
Thanks Amaniyar

[sane0394]

ok thank you
In my design I have used rivets to fix what kind of contacts I have to give to them like frictional contact and what kind of loads I have to apply can you explain about contacts and loads

[Agresh MAnekar]

I am also carrying out a similar test and when I am inserting details for drop test wizard, I am not able to see the "Next" tab and I am not able to go to next page of the setup. Can you help me with this?