Creo Simulate > Reference Links > Use Temperatures from Previous Design Study
  
Use Temperatures from Previous Design Study
Use this option in these cases:
if you select MEC/T for Model Temperature Distribution
if you want to use a previously run thermal analysis as the source for the thermal load
If you select this item, Creo Simulate takes the temperatures for the load you are creating from a thermal analysis that you run before you run the static or modal analysis.
The names of a design study, analysis, and load set appear on the dialog box. If you have multiple studies, analyses, or load sets, you can select the ones you want to use.
 
* In a sensitivity or optimization design study, Creo Simulate automatically runs the thermal analysis at each parameter setting, even if you select Use Temperatures From Previous Design Study.