Trial 4 is an effort to address the overheating issue that arose during trial 3 when one of the hair dryers shutoff from the high intake air temperature.
I speculate that the resistance caused by the intercooler core is backing up the hot air inside the hair dryer(s) and causing them to overheat.
To reduce the back pressure caused by the intercooler it is attached to the flow bench so that the bench can pull air through the core and reduce back pressure on the hair dryer.
The flow bench is operating at a low volumetric flow rate to allow hot air through the core but not pull in cooler ambient air.
The overheating problem has been addressed with this change. The temperature rise of the stock intercooler is quicker than the unassisted hair dryer, but the peak is on track to be less than what was achieved by the single hair dryer.
The next trial will be another attempt to increase the peak air temperature exiting the intercooler.