Just to chime in - Technically the more fans you add, you add more heat generation from the motors and the general principle of thermodynamics and conservation of energy. The mechanical energy will be lost via friction, and heat. In a sealed room, a fan will (at a low level) warm the room up.
As
@lionelsaid, without reducing the ambient temperature, you cant reduce the component temperature below the level it generates. That violates basic laws of physics.
To get a better temperature, you need to reduce the temp of the air. Exhausting hot air to the outside is fine, so long as that hot air doesnt find it's way back in. In my room with the window closed, the ambient temperature climbs and climbs as the PC exhausts hot air from the radiators into a mostly sealed environment. That hot air is then drawn back in to the computer intake as ambient air only its now a few degrees warmer. That air is int urn warmed up etc. etc. Eventually the temperature gets warm enough that a window must be opened - introducing cooler ambient air.
edit: Even as it gets warmer, if i turn my fans up to a higher RPM, all they do is expel the warm air quicker, and pull it in faster. All that does is decrease the time of the cycle. While moving more air over a component might reduce the temp of that component, that heat has to go somewhere - out the vents - but it cant vanish, so that warms the room up and that warmer air is taken back in.
@lionelmaybe it's just us - but this isnt exactly rocket science. Which isn't brain surgery.
at least here if im wrong somebody else will point it out 
