Hello,
You mention that you test Fluent SETUP, did you test using the same model (same mesh size, physics and setup)? The total time in the graph - Is it wall clock time or the simulation time?
In some cases, using more number of cores actually reduces the performance. See this section of the user's guide: 40.9. Checking and Improving Parallel Performance (ansys.com). I would also suggest to not display any report definitions (any graphics) while running the simulation if you are testing the wall clock time.
You are navigating away from the AIS Discovery experience