[Pierre1]

I use Workbench to run Fluent simulations. But once I start it, it seems there’s no way to either monitor the simulation or stop the simulation in the middle?

Could anyone tell me how to do them?

[miro2000]

you could pass output to a log, i.e.:
fluent 2ddp -g -i journal.jou > log.fluent
for linux. On win. I don't know

[Kokemoor]

In 15.0 and later, you can right click the Solution component in the project page in Workbench and select Show Solution Monitoring. This will plot the residuals and other monitors you've defined.

If you want to stop a solution while it's running, click the Show Progress button at the bottom right in Workbench and then the red button at the right in the progress pane.