Stephen Orlando
Ansys Employee
Hi Simon,nSo to recap, there are three cases that are being discussed. nFluent only case with some minor mesh refinements, enabling the energy equation, and changing a few physics settingsnFSI case with Fluent setup from 1.nInitial FSI case that runs in 1.5 hours.nIt's important to note that these cases are all very different and comparing the run times for them can be misleading without comparing the all the setup differences. If you attach some images of your geometry and list all changes between cases, it might be more clear why there are run time differences. There are many settings that can affect runtime so the investigation needs to start with comparing the differences between cases. Also at the end of the System Coupling log file there is a timing summary. This should give more information.n+============================================================================+n|               Timing Summary [s]               |n+============================================================================+n| Coupling Engine Time :                     2.8753E+00 |n| Coupling Participant Time                         |n|  Fluid Flow (CFX) :                      1.7293E+01 |n|  Transient Structural :                    4.2373E+00 |n| Total Time :                          2.4406E+01 |n+============================================================================+nn