When writing out partial TRN files (not full TRN files) in a transient simulation, the mass flow averaging does not function correctly, as the integration point (IP) mass flows are not stored in the partial TRN files by default. How to get this. Setting the undocumented expert parameter “mfloip to trn files = t” in the CCL will cause CFX to write out also the IP mass flows to partial TRN files to enable the user to perform mass-flow averages in CFX-Post.