Mercedes W04 Five element front wing

[PlatinumZealot]

From Gary Anderson:

"Mercedes have brought a new front wing to Jerez and Nico Rosberg is running it on Thursday. We talked about their front-wing problems earlier and this one is definitely a step forward. It is a five-element wing, but what's unusual is that it has five elements all the way from the endplates up to the start of the FIA-defined aerodynamically neutral section in the centre of the wing. The large number of elements is a good idea in front of the front tyre because the team want to have enough wing shape to give good downforce during braking, but when the driver turns into the corner, the blockage created by the front wheels is removed, and in that situation it's easy for the airflow to separate and for the car to lose downforce. The slot gaps between the elements of the wing help stop that happening. But inboard of the front wing, the more slot-gaps you have, the less downforce you can create. So most teams will have fewer elements inboard of the tyre. Having said that, it is a step forward and it will give them more consistent downforce, and less understeer mid-corner, if not perhaps more overall downforce."

[wesley123]

It's last flap seems to be running with high AoA it seems.

[Mika1]

I didn't expect they would run it today. I think it's definitely a step forward, much more details.

[Raptor22]

I don;t have CFD to examine this but having 5 airfoils will create a heck of a lot of drag. I wonder if they got the efficiency right. Pointless having a lot of downforce with a lot of drag because you'll still be slow

[wesley123]

I don;t have CFD to examine this but having 5 airfoils will create a heck of a lot of drag. I wonder if they got the efficiency right. Pointless having a lot of downforce with a lot of drag because you'll still be slow

Why would that be the case?

I didn't expect they would run it today. I think it's definitely a step forward, much more details.

Not really, instead of the tri plane wing in that area there are now 5 profiles.

[Huntresa]

I don;t have CFD to examine this but having 5 airfoils will create a heck of a lot of drag. I wonder if they got the efficiency right. Pointless having a lot of downforce with a lot of drag because you'll still be slow

Why would that be the case?

I didn't expect they would run it today. I think it's definitely a step forward, much more details.

Not really, instead of the tri plane wing in that area there are now 5 profiles.

Most teams have run 5 planes near the endplate cause running 5 whole planes casues alot of drag.

[wesley123]

Got a story of that?

My armchair expertise on aerodynamics tell me that because there is little change in overall wing design the drag increase is probably marginal. Teams tend to run only these slots on the outer section because that area is more affected by the front wheel(and it's movement). Overall a 3 plane design would be more efficient outside of that area because it got more area to work on. A 3 plane wing would generate more df, but a 5 plane wing would generate more consistent downforce.

From the few pictures I have seen it seems like the flaps run at very high AoA, this could indicate that they are trying to run more downforce with the wing design, since with the 5 plane wing they can run with higher AoA they might get more downforce out of that. And in that case, it would indeed add a noticable amount of drag.

[Rybo]

Overall a 3 plane design would be more efficient outside of that area because it got more area to work on. A 3 plane wing would generate more df, but a 5 plane wing would generate more consistent downforce.

Wasn't the previous versions, W02 and W03 specifically, very good front end wise on down force, but lacking in the rear and subsequently threw off the balance? Would this be an indication that they have resolved their issues at the rear of the car?

[Huntresa]

Overall a 3 plane design would be more efficient outside of that area because it got more area to work on. A 3 plane wing would generate more df, but a 5 plane wing would generate more consistent downforce.

Wasn't the previous versions, W02 and W03 specifically, very good front end wise on down force, but lacking in the rear and subsequently threw off the balance? Would this be an indication that they have resolved their issues at the rear of the car?

Or atleast think they have solved the rear end problems.

[Rybo]

Overall a 3 plane design would be more efficient outside of that area because it got more area to work on. A 3 plane wing would generate more df, but a 5 plane wing would generate more consistent downforce.

Wasn't the previous versions, W02 and W03 specifically, very good front end wise on down force, but lacking in the rear and subsequently threw off the balance? Would this be an indication that they have resolved their issues at the rear of the car?

Or atleast think they have solved the rear end problems.

I'm sure they think they do, but I'm sure they thought they had a grip on it in '11 and '12...

In regards to drag, the FW looks to control and refine airflow around the tire and throughout the car. The AoA will be changed for various tracks and their DF reqs. This is testing after all, and they might want to just throw everything they have available at the car and see what comes of it.

[Paul]

As mentioned, I also believe that multi-element front wings are most about down force reliability and pitch insensitivity, rather than peak down force numbers.

[wesley123]

Overall a 3 plane design would be more efficient outside of that area because it got more area to work on. A 3 plane wing would generate more df, but a 5 plane wing would generate more consistent downforce.

Wasn't the previous versions, W02 and W03 specifically, very good front end wise on down force, but lacking in the rear and subsequently threw off the balance? Would this be an indication that they have resolved their issues at the rear of the car?

Rosberg stated that he had an car that was understeering. The conditions on which it happened wasnt told, but an understeering car suggest a lack in front end grip.

Indeed, the merc lacked rear end df in previous seasons, but note that they never ran a good blown diffuser, compared to others who gained a lot of df by the blown diffuser. Now that they have a decent one it seems they have gained good rear df.

[allstaruk08]

does creating a lot of drag infront of the tyre really matter? the air in that area is already majorly disturbed by the tyre, maybe they're more directing the air flow up and around the outside of the tyre

[Raptor22]

The air coming of the wing in front of the tyre is indeed a problem but only when travelling in a straight line. When the car turns the profile presented by the tyre changes and it changes the flow conditions over the front wing.
The more planes you add, the more drag the overall wing produces so what I wold think would be beneficial are airfoil sections and AoA that allows the flow to accelerate over the wing fast enough once the blockage is removed. A highly draggy outer section isn't going to allow the airflow to speed quickly is it. I think there needs to be a balance between that wings drag vs its AoA.
If 5 planes is more efficient but more drag, is it better than 4 planes wiht less drag and slightly less efficiency? There is a relationship between drag, downforce and efficiency here so I'm just wondering if they are not over thinking the problem again