2-way coupling Ansys Rocky and Fluent

- July 27, 2023 at 7:42 pm
  
  Mehdi Salakhi
  Subscriber
  
  I have a simulation case where I need to simultaneously couple Ansys Fluent with Rocky on an HPC cluster. I was wondering if this simultaneous coupling (2-way coupling) is possible on any HPC cluster. I'd appreciate it if you could help me with this!
- July 28, 2023 at 6:56 am
  
  Marcelo Precoppe
  Subscriber
  
  While I haven't personally done the simultaneous coupling of Ansys Fluent with Rocky on an HPC cluster, in theory, setting up a 2-way simulation in Rocky on an HPC cluster should be similar to what you would do on a Windows or Linux PC. First, you need to set up your 2-way simulation in Rocky, just as you would for a simulation on your local machine. Once your simulation setup is ready, you can submit the job to the HPC cluster. When the job starts, Rocky will launch Ansys Fluent and establish the coupling between the two solvers. Just, make sure that both software packages are installed and properly configured on the cluster and that they can access the license server (if one is being used).
- July 28, 2023 at 8:34 am
  
  Rob
  Forum Moderator
  
  I've seen it done on a few client sites. We "borrow" the gpu machine and run Fluent on the cpu & Rocky on the gpu: it's more efficient and avoids conflicts with our queue system.
  One issue is queuing software. There's an option in Rocky coupling to tell Fluent where to run. So, most issues have been with cluster config rather than coupling. I'll see if one of the Rocky team can comment. Error messages will help, along with the HPC OS and whether you're using schedulers etc.
- July 28, 2023 at 1:47 pm
  
  Vinicius
  Ansys Employee
  
  Hi Mehdi, the only detail to add is that Rocky does not support distributed parallel execution. Therefore, the Rocky solver must be installed and executed in the head node, usually where the GPUs are.
- July 28, 2023 at 5:15 pm
  
  Mehdi Salakhi
  Subscriber
  
  Thank you all for helping me out!
  Is there any tutorial or documentation on running Ansys Rocky on an HPC cluster?