How to calculate average contact time for particle-wall?

Hi,

For contact time with the walls its worth considering the difference between contacts and collisions. Contacts are instantaneous values where you get the data at the specific save data point. A collision is essentially a series of contacts, and you get the whole history of the particle-wall interaction.

https://help.altair.com/edem/topics/edem_simulator/track_collision_data_c.htm

However collisions only run on CPU, they are not GPU compatible which is limiting for a lot of simulations.

You could write a custom API model to track the data which could be written to use GPU like:

Or if you want to use in-built capability you could create a bin group (lesson 18 e-learning) around the geometry, extending into the particle domain slightly. You could then track the time the particles are inside this domain, its not contact time but maybe a good workaround.

https://learn.altair.com/course/view.php?id=147

Regards

Stephen

Thanks @Stephen Cole.

I would like to move forward by using built in capability. I understand how to create bin but how to track the time of contact? Where can I find the file where the contact time is stored?

Hi, the contact time wouldn't be stored directly. You could export the particle ID in the bin group and would have to check how long that ID is in the bin. You may over predict slightly as it will just track particles inside the bin rather than contacts with the wall, unless you have a very high data save frequency.

Regards

Stephen