I think with the emergence of this new form of DDRS on the Red Bull it may be pertinent to re-phrase the original Mercedes DDRS as FW-DDRS (Front Wing Double DRS). This is due to the fact that the secondary function (Double) within their system allows the Front Wing to shed downforce/drag when DRS is activated utilising pipework that runs the length of the car.
The systems being employed by Red Bull (and possibly McLaren) can then be RW-DDRS (Rear Wing Double DRS) as their secondary function is to further enhance the properties of the rear wing region.
Lastly we have DRD (Drag Reduction Device) this is the passive system that both Lotus and Mercedes have been working on over the last few races and is now being coined as such by the mainstream media after myself and Craig Scarborough lobbied them to: http://somersf1.blogspot.co.uk/2012/09/lotus-mercedes-drd-drag-reduction.html
Above: When DRS is active an aperture is revealed in the Endplate activating another area of bodywork via tubing in the thickened Endplate (In the latest image, which is the lower of the 2 it's clear that the duct is much smaller than originally thought so is more likely the fluid switch in a larger system)
Giorgio Piola's initial assessment of the Red Bull DDRS on F1.com is a little flimsy claiming when DRS is active the airflow is sent down through the endplates and exits in the central portion of the beam wing augmenting the diffuser flow. http://www.formula1.com/news/technical/2012/878/1012.html Mark Hughes has now also added fuel to this in his article: http://www1.skysports.com/formula-1/news/22058/8151511/The-double-DRS-debate
It's worth pointing out at this stage that although the prime function that is mentioned here is drag reduction but intrinsically in these cases downforce is actually increased too. This is done by blowing a specified area in combination with an increased AoA (Angle of Attack) of the bodywork in that region. When the airflow is moved away (DRS activated) the AoA is too steep and the region stalls (downforce is reduced along with drag = Drag Reduction)
Several avenues of enquiry are available as possible reasons to use DRS as a secondary function including the one described by Giorgio and Mark above and illustrated here by Mario Keszeli
I'm unable to reconcile the above with the pictures available as no holes or slots are apparent in this region (at least in the images available)
If we are considering the Beam Wing as a plausible area to stall then we must also consider stalling the outer region of the Beam Wing (Near the endplates) as illustrated by Mario below:
In the pictures below we will see that at the moment there are no plausible area's that are being blown in order to create downforce and then reduce drag when DRS is activated:
Before we get to my idea's, an idea put forward by Petr Hlawiczka was that airflow is ejected laterally from the Endplate beside the Mainplane as he showed us in this picture and illustrated by Mario:
Lastly I have two idea's of my own both of which come from my own thoughts on how to use DDRS and my investigations into the possible application that McLaren have been using since Spa
I floated the idea after Spa of McLaren using a form of rear wing DDRS with their Top Flap having hollow sections allowing air to be re distributed when DRS is activated to uncover the holes in the endplates. At that point I had no further proof as to what McLaren were stalling/moving air to/away from in unison with DRS but it was also apparent there was a slot on the trailing edge of the top flap.
Blowing the trailing edge will speed up the flow on both the front and rear surfaces of the plane enabling them to run a higher AoA which in turn creates more downforce and a more efficient wing. You'll notice they have large gurney tabs on the Top Flap to accentuate the effect of the trailing edge blowing.
Working along a similar vein as the original F duct system this makes the Rear Wings top plane more efficient with airflow from the engine cover running internally through the Beam Wing and up the endplates to the hollowed top plane where the air is ejected. McLaren's trailing edge slot features a wider section at the tips of the plane which I believe blows more to further reduce wing tip vortices.
When DRS is activated the blown effect is simply ejected laterally from the Endplate joining the free stream that feeds between the gap opened by DRS. It may also be possible to use dynamic stall within the wings design here in order to increase downforce momentarily before the vortex that's been shed reaches the trailing edge. This would enable DRS to be opened momentarily in advance of it's usual operation window = more planted/stabilized car when DRS is activated and a quicker qualifying lap.
I have insufficient pictures of the RB8's Rear Wing from Singapore and Suzuka to see if they have a similar slot on the trailing edge of the Top Flap to ascertain if they are too running a similar design.
Lastly we all know that the manipulation of exhaust gasses is the best way to increase rear downforce and will contribute to much better rear tyre life/degradation and so using a system to control the exhaust plume would be hugely beneficial. Once again I have looked through many pictures of both the MP4-27 since Spa and the RB8 since Singapore and can't find the definitive answer (But based on Piola & Hughes articles neither have they)
In this last and possibly the most intriguing idea I believe they could channel air from the Engine Cover through the Beam Wing across to the Endplate and blow the air out of the side/rear of the endplate. The idea behind this is either to create an air dam forcing the exhaust plume to follow the contour of the coke bottle over the top of the diffuser. Or use the Coanda effect to manipulate it's flow inbound. This will make the diffuser more efficient and bring rise to a style of EBD the teams lost under the 2012 design regulation changes.
Above: RB8 possible placement of rearward blowhole consistent with the team reducing the size of the endplate strakes when the new wing arrived in Singapore (This hole does seem to appear on other photo's too but it could also be a light reflection) The lower image is from Korea.
One things for sure the appearance of RW-DDRS on the RB8 has raised more questions than answers for me but I'm fascinated to see how the RW-DDRS uses both the additional downforce and drag reduction it has been designed for. The question also remains with only 5 races left and the title about to go to the wire does anyone else have a RW-DDRS up their sleeve?
EDIT 17/10/12 - Today I have added a new article on Red Bull's DDRS: http://somersf1.blogspot.co.uk/2012/10/red-bull-rb8-rw-ddrs-plausible.html