Rob
Ansys Employee

You''ll need to post the images into the thread as staff aren't permitted to follow links and/or download files. 

Otherwise, if the iodine is added as a volume fraction at the inlet and nothing happens to alter the period when iodine is added (ie a short tracer pulse) then the whole domain will show a constant volume fraction. So, the residual might not change. The critical panel is the inlet, and specifically the species tab.