Recirculating Fan - (AKA Gasper Fan)
Also gives cabin inhabitants the illusion of incoming
air with packs off. And yes, this does add more humidity to the passenger cabin. Flight deck usually gets 100% outside air.
Barit1, are you refering to the novel electric prssurization system?
anyone have more info about this system's philosophy?
Not sure of exact scheme of air production - but I can tell you that the RR Trents for the 787 have 2 starter/generators fitted that combined generate 1/2 Megawatt from each engine.
RE:707 - Turbo-compressors - basically what it says - with the pressurized
inlet air isolated from engine air. This was done to ensure cabin air quality. At that time they thought the engines might spew kerosene fumes into the system in
everyday operation.