Red Bull RB5

[DaveKillens]

Sorry this link is not working.

Go figure, it doesn't work now, even though it did when I made the post.
Here is the HTML version, sadly without illustrations of graphs.
http://74.125.113.132/search?q=cache:kf ... clnk&gl=ca

Anytime any component is changed in relative position, it has to take energy to do it. That energy has to come from the drivetrain power, thus it removes from total output power. This is one of the many factors that rob a drivetrain of power, and any reduction or elimination adds to performance.
My point is that this also leads to heat buildup inside the CV joint. The more power, the higher revolutions, and angular displacement contribute. Considering that the inboard CV joint lives in a very hot and harsh environment, this would contribute to failure. I would like to know exactly which CV joints on the Red Bulls have failed, and my bet would be that it is in the inboard CV joints.

[RacingManiac]

it was my understanding that it was a boot/seal failure which causes the CV to overheat because it causes a loss of CV grease, which I am actually guessing its outboard since they tend to be more prone to tearing....Boot failure a lot of the time is a result of the articulation angle...I remember in 2005 or 2006 in Daytona 24 one of the Porsche powered car had the similar problem because their output location out of the gearbox is different from many of the other cars and they tore their drive shaft boot 4-5 times in the race....

I don't think the energy consumption of the CV caused by the alignment angle is THAT big of an issue. I can see where you are coming from, but the friction dealt with the CV shouldn't be different since the whole idea of the constant velocity joint was that there is no speed differential. The amount of bearing used is the same. And assuming that the kinematic was designed properly(and at this level they should be), the amount of driveshaft movement in plunge should be well controlled. Where as the rubber boot is actually undergoing more stretching relaxing if it is at a more extreme angle, which may fatigue quicker.

[ESPImperium]

Im gonna throw another variable into the CV joint thing with the RB5 exaust location in relation to the rear axle. I feel that could be another part of the problem.

However, here is what Red Bull has replaced in Parc-Ferme at each race so far:

Australia:

Car 14:
Upper fixing screws and nuts between the airbox and roll hoop
RHS front wheel cover and nut assembly

Car 15:
Upper fixing screws and nuts between the airbox and roll hoop
RHS upper bargeboard stay
LHS floor stay
Upper rear wing assembly
Brake pipe support grommet

ECU Software Version: 1.00.050

Malaysia:

Car 14:
Rain light
RHS front brake drum pushrod foam seal
RHS front brake drum to wheel foam seal
LHS front wing outer flap gurney
Two tyraps under the RHS radiator duct that hold the chassis loom

Car 15:
Velcro which attaches the driver leg padding to the inner surfaces of the chassis
LHS front brake duct body

ECU Software Version: 1.00.050

China:

Car 14:
LHS front wing gurney
LHS upright / driveshaft assembly
RHS inboard driveshaft boot
LHS backing ring bolt

Car 15:
LHS upright / driveshaft assembly
RHS inboard driveshaft boot
RHS upper barge board bracket

ECU Software Version: 1.00.050

Bahrain:

Car 14:
Pitot assemblies
Tridair engine cover receptacle
Edge seal for the clutch cooling duct

Car 15:
RHS rear brake disc temperature sensor
Two screws which attach the floor pressure sensor cover and securing the sensor to the floor
LHS floor loom

ECU Software Version: 1.00.054

Spain:

Car 14:
LHS front brake duct drum foam seal
Upper water radiator AV mounting grommet
Two screws used to attach the lower T-tray stay mounting bracket to the stay
ECU cooling duct retaining O-rings

Car 15:
Two anchor nut plank fixings
ECU cooling duct retaining O-rings
Pedal assembly

ECU Software Version: 1.00.056

Monaco:

Car 14:
RHS front brake drum outer foam seal
RHS rear top wishbone forward leg closing panel
Tyrap on floor that secures the wiring loom

ECU Software Version: 1.00.056

Just some more usless data i have from Jo Bauers official reports and my own data charts.

[kNt]

I think that the RB5s will go back to launch spec for Turkey, just looking at that sticking plaster design.

Those scoops just arnt doing it for me. What they (Newey) need to do is this:



Make air flow come allong from the central section of the floor and enter from the side of it, making the central section of the difuser as efficent as posible to increase downforce that way. Im thinking that posibly the Mclaren floor cuts may also help with the efficency of the outer extremities of the diffuser as theres more air getting under the floor for this to help.

I dont have the CFD or windtunnels to run the simulations, but i can see that helping from my point of view.

Inside the upper deck of the diffuser flows along your green line I guess. But I think this deisgn might be quite clever, surface closer to the ground in the diffuser creates more downforce and redbull have more surface with a ddd than most other teams, they don't sacrifice a lot to feed the holes.

[bonjon1979]

I'm not sure it's possible to do what you suggest because of the standardised wooden plank that all cars must have on the bottom of the car. The green lines you've drawn cut the corners off this.

[Shi Ruan]

I'm not sure it's possible to do what you suggest because of the standardised wooden plank that all cars must have on the bottom of the car. The green lines you've drawn cut the corners off this.

I could be mistaken, but I believe that represents internal flow.

[BreezyRacer]

Keep in mind that the Newey design is laid out to use the scoops as the access to the low pressure area under the lower wing element. That is used to "suck" the bottom of the car. Also keep in mind that these planks run right on the ground so basically the car is divided into right and left sides. This is quite useful in keeping downforce in yaw. Look at the entire car .. RB have isolated the sides of the car with the ducting as well wings, etc. Does the DD work? I think so but it might need some tuning in terms of planning the double diffuser exit in correlation with the lower wing element.

I'm sure the inlets at the bottom of the car are carefully done. You only notice it if you study it, but they reshaped the entire center section of the bottom, they didn't just take on scoops.

I find it interesting to see that some time during the Monaco weekend they trimmed down the gurney flaps directly behind the upper exits of the double deck diffuser. Maybe that wasn't the best choice ..

I think that the RB5s will go back to launch spec for Turkey, just looking at that sticking plaster design.

Those scoops just arnt doing it for me. What they (Newey) need to do is this:



Make air flow come allong from the central section of the floor and enter from the side of it, making the central section of the difuser as efficent as posible to increase downforce that way. Im thinking that posibly the Mclaren floor cuts may also help with the efficency of the outer extremities of the diffuser as theres more air getting under the floor for this to help.

I dont have the CFD or windtunnels to run the simulations, but i can see that helping from my point of view.

Inside the upper deck of the diffuser flows along your green line I guess. But I think this deisgn might be quite clever, surface closer to the ground in the diffuser creates more downforce and redbull have more surface with a ddd than most other teams, they don't sacrifice a lot to feed the holes.

[BreezyRacer]

BTW, no one has said anything about the RB wheels, surprisingly. Quite a different approach there. I wonder if they leave a better wake pattern or maybe even generate a little df.

[kilcoo316]

Also keep in mind that these planks run right on the ground so basically the car is divided into right and left sides.

Be careful with that.

On braking the back of the plank definitely isn't on the ground.


Screw that up and your car can become very pitch sensitive and hence slow.

[Scotracer]

And remember the rear of the car sits higher than the front. At medium-low speeds the plank definitely isn't on the ground...

[BreezyRacer]

Yep .. when I say on the ground I'm saying that the air space to the plank is minimal. For ground effects to work you need some air movement. It seems that when the floor gets within 15-20 mm of the ground it stalls out, so even though you can see some daylight there it's dead air space, which is to say useless for ground effects. In the early days of ground effects downforce would disappear suddenly when the air gap closed up too much. Of course, just before that the downforce was really great ..

Also keep in mind that air will flow to it's lowest pressure area so think of the under tray air being sucked from the diffuser rather than being rammed from the front of the car. A little of both is happening but many people have a problem thinking about air being pulled from the back of the car's low pressure areas. The ducts on the RB5 DDD look more interesting when you view them in that light ..

Also keep in mind that these planks run right on the ground so basically the car is divided into right and left sides.

Be careful with that.

On braking the back of the plank definitely isn't on the ground.


Screw that up and your car can become very pitch sensitive and hence slow.

[megz]

BTW, no one has said anything about the RB wheels, surprisingly. Quite a different approach there. I wonder if they leave a better wake pattern or maybe even generate a little df.

With the asymetric camber you mean? I think the left rear generates more drag being out in the open air rather than being behind the front tyres...

[kilcoo316]

A little of both is happening but many people have a problem thinking about air being pulled from the back of the car's low pressure areas. The ducts on the RB5 DDD look more interesting when you view them in that light ..

I still think they are losing out by not getting the acceleration (due to the ramp) on an exposed surface.



I previously suggested (some other thread) that teams might look at perforating the whole step running most of the length of the floor and suck air in over its whole length, rather than concentrate the lot at the back of the car.

In hindsight, it was a pretty crap suggestion, while it does get more air under the car, it means you gain less by not adding to the longitudinal velocity, and you lose more by inducing a transverse velocity = more massflow coming in from sides.

[BreezyRacer]

A couple of things here .. changing the direction of the air flow too abruptly pretty much negates any acceleration of flow. Keep in mind that accelerating the air flow towards the rear of the car is designed to produce low pressure over the entire under tray surface area, at least in a well designed under tray and diffuser. Everything is critical .. the inlet area ..isolating air flow from the entering the under tray area along the sides .. making the diffuser pull forward enough in the chassis to create a low pressure area as far forward as possible, ensuring that yaw movements won't cost too much in lost downforce, etc. The fact that RB created a whole new under tray for this diffuser is pretty telling. This is not a patch or something tacked on, and I'm impressed that what they have is very tuneable as well with the interaction of the ports and the lower wing element. While you cannot judge the outcomes by just looking at the pics I think it's safe to say that RB have spent a lot of time on this redesign. Newey knows very well (better than any of us) what he's doing. Also keep in mind that this change coincides with the new CF grearbox. I bet the packaging exercise on this deal was very hairy and involved all this coming together .. we don't know what the inside of those ports look like .. how straight and open they are .. I soo would love to see that up close and I'm sure I'm alone in that desire ..

A little of both is happening but many people have a problem thinking about air being pulled from the back of the car's low pressure areas. The ducts on the RB5 DDD look more interesting when you view them in that light ..

I still think they are losing out by not getting the acceleration (due to the ramp) on an exposed surface.



I previously suggested (some other thread) that teams might look at perforating the whole step running most of the length of the floor and suck air in over its whole length, rather than concentrate the lot at the back of the car.

In hindsight, it was a pretty crap suggestion, while it does get more air under the car, it means you gain less by not adding to the longitudinal velocity, and you lose more by inducing a transverse velocity = more massflow coming in from sides.

[vasia]

Interesting slit along and below the shark fin, likely for cooling.