Launch Analysis: Red Bull RB8

Car: Red Bull Racing – Renault RB8
Concept
There’s not a lot left to be said about Red Bulls incredible run of pace since 2009. Despite not winning the 2009 championship, the RB5 rewrote the text book on F1 design. Since then, the two subsequent cars have both pioneered new ideas and followed a few others. Each time the car has been ever more dominant. If the team have an achilles heel, then its reliability, split between the; chassis, the engine and KERS. With pace in hand, the team do not need to make bold steps with the cars design, as they need to maintain reliability. With the RB8 taking risks was not on the agenda, the evolutionary car uses detail design and a small few unique features to keep a step ahead on pace.

Layout
With the evolutionary concept, no obvious changes have been made with the cars layout.  The retains a steeply raked attitude, Newey mentioned at the launch that the loss of EBDs will affect their ability to angle the car into the nose down attitude.  But the evidence of the car on-track suggests that obtaining laptime with a lot of rake is not an issue.

Nose

As with many teams, the nose grabbed most attention when the car was launched. But rather than the shock from the awkward looking 2012 noses, there was curiosity over the letter box slots in the nose. There was one more visible slot on the upper section of nose and one less visible one below it.
Rumours circulate that the upper slot is used for some form of F-duct or (non driver) cooling. In my opinion, it is a simple solution to keep the airflow attached over the step in the nose.
Faced with the 2012 rules, Red Bull took the obvious route of a raised chassis and nose. The car now eschews the “V” shape nose and chassis, so the top of the chassis and nose are flat. With the rules forcing a 75mm step between these two surfaces, the airflow doesn’t want to run along the nose and then step up without separating from the chassis top.

So the team has sought to offset some of problems with this design. Red Bulls solution is to create an aero effect to aid the transition between nose and chassis. This starts with the letterbox inlet, which as Newey explained at the launch is ‘primarily’ for driver cooling. The rules permit one opening to the nosecone for the purposes of driver cooling. Normally this is an oval hole in the tip of the nose. But on the RB8 this is a 25cm wide narrow slot and probably only 5mm or so high. As Newey admits, some of this airflow does pass into the cockpit to cool the driver. But what Newey would probably describe as the secondary effect of the slot, is to allow for the rounded leading edge above the inlet. When airflows runs up the nose it hits this leading edge and curls under it, forming a bubble of recirculating flow. This rotating cylinder of airflow helps to keep the upper airflow aligned and attached to the flat top of the chassis. This is a simple and copyable solution. I believe this would work with or without the slot. As the upper section of nose cone bodywork is largely a cosmetic panel and not part of the crash structure. It could be changed without re-crash testing. Sauber have found a similar solution on their nose.
Below the nose there is yet another slot. This in line with the bottom of the chassis and runs the full width of the nose. While I can offer some explanation for the upper slot, this lower one is more of a mystery. Again its use has been rumoured as KERS cooling or blowing the floor, whatever its function I believe it may have been on the car last year. Although the slot was not externally visible on the 2011 car, when the nose is removed the slot was evident below the front bulkhead (pictured below). Presumably this was fed from the driver cooling inlet, which was placed on the nose tip on the RB7.

Clearly the duct formed is very small, which limits it use. I doubt it’s to cool KERS, as the KERS is mounted towards the rear of the car and the small duct would not adequately cool batteries or the like. Its position does suggest the flow could pass down to the splitter, so some clever use for blowing or loading the splitter could be within the realms of possibility. More likely is the use to cool the electronics or power steering rack, which are sited much closer to the duct and would require a smaller amount of cooling air.

One detail of the RB8 and to an extent with the RB7 was the advantage it takes of the radius that is allowed to be applied to the edges of the chassis. This 25mm radius is rounded over to keep the cross section of the nose as small as possible. Within the minimum 300mm x 275mm rectangle the nose must fit into. The top corners of the chassis are clearly a near 3/4 cylindrical section.

Front wing

In common with their rivals the front wing is a derivative of the 2011 wing. Albeit restructured to meet the newly doubled deflection test. Red Bull were late to the endplate-less wing design. Although they created slot in the endplate over the past few years, it’s relatively recently they upper section of endplate has been added on to the tips of the wings, rather than use a conventional separate endplate.

Behind the wing the turning vanes continue the mid 2011 ‘curled’ design.  The vanes hang from below the chassis and are larger this year and sport a split in the middle.

One odd feature visible on the front wing is a small section of removable bodywork in the neutral centre section of wing.  I’ve idea of the purpose of the purpose of this panel, perhaps its to access a sensor or allow ballast to be fitted?

Roll hoop

While retaining the same engine and with the general evolutionary theme of the car, the roll hoop area is indistinguishable from the 2011 car. No doubt there are structural changes under the skin, but these aren’t visually apparent or announced by the team.

Sidepods\Cooling

Moving onto the sidepods, the general concept of the sidepod shape is also similar to 2011. Slightly triangular inlets feed the radiators, which are mounted horizontal across the car and tilted upwards towards the front. Their flow passes up and around the heat shielding on the engine\airbox and most of it exits through the tail funnel. In cross section the sidepods retain the outwardly-tapered ‘jelly mould’ appearance, with only the area under the inlet being undercut. Again as with the RB7 the sidepods merge seamlessly into the gearbox fairing.

Exhaust

Traditionally Red Bull have switched their launch exhausts to their Melbourne spec in the last days of testing. It’s been mentioned by the team that there is a new exhaust system coming. This is no doubt partly the reason for the team delaying the last test and having a near private test (shared with Ferrari) on the last day.
The launch spec exhaust places the outlet pipe inboard and relatively low. This bows in line with the plane of the rear upper wishbone. The bodywork over the gearbox and rear crash structure is curved and creates a neat channel for the flow to pass through. This then sees the exhaust plume pass under the beam wing. In this position the heat is affecting the upper wishbone, even at its launch, the car sported heat shielding over the wishbones. During testing this protection has grown, albeit with temporary looking solutions, suggesting the new exhaust system will not blow in this area.

Rear suspension

The RB8 has a high mounted upper rear wishbone, which places its rear leg in line with the beam wing. In keeping with the recent RBx cars, the gearbox sports a tall spine that functions as the wishbone and beam wing mounting. Although this shaping is partly hidden by the way it merges into the tail funnel.

With such a high top wishbone the lower rear wishbone is able to mount higher too. This wishbone is now effectively at the same height as the driveshaft. Not only is it inline, but the wishbone forms an shroud ahead of the driveshaft to offset the negative aerodynamic effect of the rotating shaft, in the critical area above the diffuser (Note: Fully shrouded driveshafts are banned). While this all appears to be logical, the lower wishbone is not a splayed as the upper wishbone. Having the inboard mountings very close to each other is not so good from a loading perspective, so there must be a reason to make the wishbone in such a compromised shape. Again this might suggest the new exhaust needs the wishbone in a certain position to work effectively.
Diffuser\rear impact structure
With the tapered sidepod, the Red Bull encloses the centre of the diffuser inside the gearbox fairing. Other teams leave this exposed beneath the crash structure, to allow flow to pass through and out of the starter motor hole. Last year Red Bull introduced a duct in the floor to send flow directly to the starter motor hole. This year the duct appears to have gone and doesn’t look like it’s been replaced with something. In line with the gearbox and the current exhaust set up, the impact structures forms a spine along part of its length. Once the beam wing is mounted to the spine, the crash structures returns to a normal rectangular cross section and sweeps upwards towards the tail light. This spine format keeps the gearbox and suspension mountings nice and stiff, plus it mounts the beam wing with very little obstruction to it slower surface.

Gearbox
Red bull have used pull rod suspension since 2009 and introduced their carbon fibre gear case in the middle of that year. Keeping the construction and general shape, the gearbox set up appears only have detail revisions over this period.

Aerodynamic features

Every team has exploited the 12cm of space inboard of the rear wheel for aerodynamic bodywork. Red Bull have added particularly large upper vane to the brake ducts this year. Above the top wishbone mounting two large flap can be seen.

The rear wing also exploits a small window that allows bodywork, this makes it possible for Red Bull to fit vanes placed behind the diffuser, to aid the expansion of the flow out of the diffuser.

KERS
It was a bold decision in 2011 for Red Bull to develop their own Battery system for the Renault Marelli KERS. Not wanting to sacrifice wheelbase and fuel tank volume with under-tank mounted batteries, instead Newey mounted the batteries near the gearbox. In fact three batteries packs were fitted, one larger pack either side of the gearbox and a small array inside the top of the gearbox case. Exposed to more heat and vibration the KERS caused problems throughout 2011 and led to the driver having it unavailable at critical points in qualifying and races. I understand the battery positions remain for this year. It was never clear if Red Bull actually had a full power KERS in 2011. The rumours persisted of a Mini-KERS, suggesting the system discharged nearer 40Kw, rather than the maximum allowable 60Kw.

Engine
Announced in mid 2011, Red Bull are now the official ‘factory’ team for Renault. With the success of the team and the Renault F1 team being rebadged to Lotus, This allows Red bull to take a more direct involvement in developing the RS27 engine and the exhaust mappings to maximise what is allowable in the rules.

Launch Analysis: Ferrari F2012

Car: Ferrari F2012
Concept
Having followed a very similar concept since the 2009 F60, Ferrari found in 2011 that the conservative route was not making up the ground to their rivals. The F150 was a fast car, but lacked that final ounce of pace to beat the Red Bulls and McLarens. This was exacerbated by the car being easy on its tyres, to the point where it had tyre warm up issues. This showed itself in qualifying were the car would not make the most of a tyre around a single lap and also in cooler weather, or where the harder Pirelli tyre was used. The team recruited Pat Fry in a major reshuffle of engineering staff. Fry spent the year assessing Ferrari problems and set about a recruitment programme of new staff and a more adventurous design programme. The resulting car is clearly very different from its predecessors.
Externally very little remains the same on the new car, it does perhaps shares Ferraris favour for a long wheelbase and clearly is set up to run a fairly steep rake angle. But only the front wing, which is derived from the late 2011 wing appears to be carried over. Even this detail was a development in preparation for 2012, Fry leading the team to follow Red Bulls format of front wing in both shape and aero elasticity.

Layout
With a similar wheelbase, the revised seating position is perhaps the only change to the cars layout. The seating position was altered for Fernando Alonso last year and has been altered once more for a lower position.

Nose

Of all the 2012 front ends Ferrari has one of the most striking, the nose being very wide and square in cross section. The width is part of philosophy to use the extended wing mounting pylons, as a pair of turning vanes cascaded with the normal undernose turning vanes. By making the nose as wide as possible within the space allowed within the regulations, more undernose surface can be used to accelerate air through the duct formed by the nose and vanes. As a result the edges are tightly radiussed and cannot be rounded as with other teams. The aesthetics of the nose being also worse for the rectangular cross section front bulkhead. Ferrari opting not to make a “V” shape of the bulkhead, in order to make the area under the raised chassis uncluttered to make the vane set up work most effectively.

The flow through this vane set up starts with the wing mounting pylons, these are wide spaced at their leading edges and they then converge to end inboard of the main turning vanes. The main turning vanes then pick up the flow accelerating between the pylons and sweep out to direct the flow towards the lower leading edge of the underfloor.
Curiously Ferrari has yet to fit a driver cooling vent into the nose. This hole is not mandatory and clearly not a requirement for a chilly Spanish pre season test.

Front wing
As previously mentioned, the front wing is a derivative of the late 2011 wing. This was extensively detailed in a previous post. The wing is a three element set up, the main plane being slotted to create the leading two elements, and then the flap trails this. An extra slot in the down-turned corner of the flap helps keep flow attached in the steepest section of wing. The footplate is formed by the wing curving down on itself, while the upper section of endplate is a separate vane, albeit joined along a lot of its length to the foot plate. Front wings are now subject to a doubling of the deflection test used by the FIA 2011. So far the Ferrari wing has not exhibited the flutter seen last year, which is not to say it is not flexing.

Front Suspension

A mention of front suspension in the cars launch analysis will be unique to Ferrari this year, as they have revisited an old direction with its layout. Every other car for well over ten years has had pushrod front suspension, but Ferrari has revived the pullrod set up for the front of the car.

This effectively turns the pushrod set up upside down, now the rod passes down from the upper wishbone and connects with the rocker, which is now mounted at the bottom of the chassis. According to Fry, this set up is a little lighter and has a slightly lower Centre of Gravity. These gains alone will not pay for the systems inclusion on the car, so the team claim to have found an aero benefit. The pullrod can be thinner, but the real gain is the pullrod is mounted near horizontal across the front suspension. This places it in line with the upwash from the front wing. Just as with the wishbones, its profile can be subtly altered within the rules to help control the wake from the wing and improve the airflow over the rear of the car. Despite appearances the pullrod is as effective in moving the rocker for a given wheel travel as a pushrod. The important factor is the angle between the rod and the wishbone is connected to, rather than the rods angle to the chassis. I’ll explain a lot more pull rod suspension in a subsequent article.

Roll hoop

Although not a performance differentiator, the new roll hoop is very different concept to that seen in previous Ferraris. A far curvier pair of inlets are formed by the structure, this shaping being at odds with the ungainly nose. It is strange Ferrari have not undercut this area and exposed the structure supporting the roll hoop, which is the common practice to achieve more airflow to the rear wing. The main inlet feeds the engines airbox, while the smaller inlet piggy-backed behind it, most likely feeds the gearbox and hydraulic oil coolers mounted above the gearbox. The lifting point for the trackside cranes is formed by beneath the main inlet and enclosed by a simple bar connecting it to the top of the chassis.

Sidepods\Cooling

It’s perhaps the sidepods that are the big performance area for the car this year.
Starting at their leading edge, the car sports a new format Side Impact Spar (SIPS) design inside the bodywork. Since 2009 Ferrari had a staggered SIPS arrangement, with a narrower spar sat ahead of a wider spar, creating the distinctive peaked sidepod inlet. Now it spears a single spar spans the sidepod and protrudes through to form the mount for the sidepod vane. This allows the spar to be wider, which creates an easier job to absorb the impact. Viewed from above the sidepod inlet lean inwards. This makes them more efficient at meeting the diverging flow that passes around chassis to enter the sidepod.

Much smaller and far more undercut, the sidepods now feature radiators mounted upright and splaying outwards from the rear of the car. Their new placement allows the flow through the cores to be directed outboard, rather than in towards the central tail funnel. This heated flow from the radiators passes out through the downswept chimney-fairings that differentiate the car from its rivals. This design keeps the centre of the car as slim as possible, with there being no tail funnel to obstruct the rear wing. Airflow passing through the undercut in the sidepod, still enters a coke bottle shape below the chimney-fairings and is passed over the diffuser. But these chimney-fairings also have a more important secondary use, for housing the exhaust outlets.

Additional cooling outlet area is provided in the tail of the sidepods, in between the rounded end of the chimney-fairings and the gearbox fairing. This gearbox fairing is nearly round in cross section also forms an outlet for hot air to exit from the engine bay.

Exhausts
With floor level exhausts no longer allowed, the teams have had to find different ways to make use of the powerful exhaust plume. Most teams have directed it over the sidepods towards the centre of the beam wing, but Ferrari have purposely placed the exits as far outboard as allowed (on the launch spec car at least). When viewed from above its clear these are aimed outboard of the rear wing endplate.

Sat inside the downswept chimney-fairings, the exhaust at first might be thought to be pointing downwards. But the rules state the exhaust outlets have to point upwards by at least ten degrees. Although not visible inside the chimney-fairings, the last 10cm of exhaust do indeed point upwards.

But the cleverly the down sweep of the chimney-fairings creates a downwash effect over the exhaust plume and this directs the combined flow downwards between the rear brake ducts and rear wing endplate. This set up will potentially reach the floor and act to seal the diffuser from the ground as with the 2011 EBD.

In testing the set up has gone through several iterations, firstly the exhausts exits were in line with the end of the chimney-fairings, but soon the exhaust tail pipes were shortened and the chimney-fairings above had to be cut back to maintain legality and also the allow the downwash flow to reach the shorter tailpipe.

At the Barcelona test the exhausts were again altered, this time being brought further inboard, approximately in line with the channel formed between the chimney-fairings and the engine cover. Now the exhausts appear to point inboard of the rear wing endplate. It’s not clear if this is an aerodynamic decision or a request for a less obviously aerodynamic solution from the FIA. Should the exhaust outlet stay in this position the sidepod and the chimney-fairings will need to be altered to optimise the downwashed airflow around the tail pipes.

Rear suspension
Almost unspoken of amidst the talk of the front pullrod set up, Ferrari also switched their rear suspension on its head and gone for pullrod on the rear of the F2012. Last year we saw the Ferrari had a very complex setup around the rear suspension rockers and placing this hardware lower down around the clutch and engine drive shaft, will be a tough task package.

Mounted to the revised gearbox, the rear top wishbone has been repositioned this year. It appears to be nearly horizontal; this places it in line with the beam wing, so the wishbone can act as a flow conditioner ahead of the wing. Even if the new gearbox is not as low as the Williams, the wishbone needs to mount to a vertical extension above the gearbox. This wishbone mounting hard point also forms the mounting for the beam wing. At first this appears to be a duct, but is just the thick swan-neck mounting similar to that used by Marussia for the past two years.

Diffuser\rear impact structure
Within the bodywork rules, there is not a lot of scope for a very different diffuser. So Ferrari have now added a full width flap around the diffuser on the new car.
Unusually Ferrari have not fully exposed the underside of the beam wing above the rear crash structure. Looking at the crash structure itself its clear it is shallow enough to allow this. Instead the crash structure has additional bodywork above and below it, which merges it with the beam wing.

Gearbox
As already mentioned the gearbox is a new design. The hybrid carbon and titanium case now has to mount a very different rear suspension system, with the switch to pull rod spring\damper operation and the raised upper wishbone.
Last year Ferrari were notable for having a single selector drum for their seamless shift set up. Most teams use two selectors; each one operating alternate gears, so that the phasing from one gear engaging and the other disengaging can be adjusted. Ferrari with a single selector must be confident that their system can always shift with the same aggressive phasing, without the option to go for a longer overlap.

KERS
Ferrari develop their KERS with Marelli, the system retains the same layout as in 2011 with the MGU mounted to the front of the engine and the Batteries placed under the fuel tank. The power electronics reside in the right hand sidepod.

Engine
With the engine freeze, not much can be said of the engine. Ferrari have usefully provided a high resolution image of the 056 engine, complete with integral oil tank, but lacking the KERS MGU.

Blog Update: More posts coming soon

I just wanted to post a quick update about the blog. You will have noticed I’ve not posted any new articles since the McLaren launch, meanwhile my work is appearing in other places.

I’ve been lucky to have my work published in several places this year, Autosport.com being the most notable one, but also several magazines including Motorsport, Racecar Engineering and Autosport (Japan).

As my Autosport articles appear in the Autosport ‘Plus’ section, which is the subscribers section, many of you have voiced concern my work will again disappear behind a paywall. I hope my work does appear more regularly in Autosport.com, but this will not be the alternative to my blog.

I have not forgotten the blog. My published work along with the video clips recorded for ‘The Flying Lap’, numerous tweets and the day job, mean I am simply struggling to find time to complete the words and in particular the illustrations for the blog. I have all the cars analysis coming over the next few days, plus some specific features on the trends we’ve seen so far on the new cars.

Thanks for your patience, normal service will resumed shortly.

Scarbs

Launch Analysis: McLaren Mercedes MP4-27

As the first real launch of a 2012 F1 car, McLaren have unveiled their MP4-27. In McLaren parlance this was the cars “technical launch” and was carried out at their Technical Centre in Woking, UK.

2011
McLaren had one of the fastest cars in 2011, on its day the MP4-26 was faster than the Red Bull. So the basic approach of the new car did not need to veer too far from direction McLaren had been following. Last year the season was blighted by poor form in pre season testing. Most of the winter tests were interrupted by exhaust problems, as the now near mythical “octopus” exhaust broke after a few laps out on track. This exhaust turned out to be far simpler than the rumours suggested. The exhausts ran sideways across the floor to exit in a longitudinal slit ahead of the rear wheels. This being a complex way to achieve the same sort of fluid skirt that Red Bull achieved with their outer blowing exhaust layout. Once McLaren had followed Red Bulls lead with the exhaust, they were able to catch up. McLaren perhaps even surpassed Red Bull with the exhaust blown diffuser, as the Mercedes Hot Blown engine mappings were superior to the Renault cold blown solutions. Despite the rules trying cap the hot blown benefits as early the Canadian GP, the Silverstone GP weekend showed how much McLaren were lost relative to Red Bull when the restrictions really bit hard.

Philosophy
With a strong car at the end of 2011, the team have learnt about the damage a slow start to the year makes to their championship chances. This year evolution is required, McLaren do not need to find large chunks of time, but do need a car that will perform well at the opening races. Thus we see the refinement of old concepts and little in the way of radical development.
Thus the new car bred from the recent line of McLarens, the family resemblance goes further than the colour scheme. With a low nose and sweeping lines over rounded sidepods are now trademarks of the Woking design team. With the second year of the fixed weight distribution and Pirelli tyres, little needed to be done to the cars basic layout. Running much the same chassis, fuel tank size and gearbox, so the wheelbase is similar to the previous car.
Although the 2012 Pirelli front tyres are a new shape tyre, Paul Hembury from the tyre supplier confirmed to me that the change in the new profile is “not visible to the eye”. So only small optimisations of the front end aero are needed to cope with the change.

The nose-down, tail-up 'Rake' of the car is evident, with as much as 10cm of rear ride height

The studio photos of the car in side profile show off the amount of rake the car is designed to run. This is also a carry over from 2011, as the car could often be seen with a clear 10cm of ride height at the rear axle line. Although managing rake will be harder this year as the greater rear height introduces more leakage into the diffuser from the sides. As yet the teams solution to seal the diffuser are hidden by a simple floor fitted to the launch, although these are removable panels and more complex designs will soon be seen.

With so much to carry over in philosophy and design, what has changed for 2012?

MP4-27 in detail
The stand out points on the MP4-27 are the nose, sidepods and exhaust position.

Firstly the front wing is near identical to the late 2011 wing, so we can expect its general design to carry over, as will the snow plough vane below the nosecone. But the height of the nose at first appears to be at odds with the 2012 rules on a maximum 55cm height for the front of the nose.

Looking closer at McLarens chassis in side profile its clear the family history of low noses has helped here. The dashboard bulkhead is may be just 3cm higher than the cockpit padding (which is 55cm high), the chassis top then curves downwards towards the front wheels. By the point of the front (A-A) bulkhead the top is lower than 55cm, may be as low as 5cm below the maximum height. When compared to the maximum heights (the dotted line on the drawing), its clear this is a very low nose overall.

The snow plough vane under the nose might be part of the secret to a low nose

This creates less space under the raised nose, but the teams snow plough device under the nose works aggressively as a turning vane, so perhaps the team don’t need the higher chassis to get the correct airflow to the sidepods leading edge. McLaren also find the lower nose provides the classic vehicle dynamics benefits of a low CofG and a less extreme front suspension geometry. This trade off works for McLaren and goes to prove not everything in F1 has to be a compromise in search of aero advantage.

Unique drillings between the rim and spokes of the wheel aid brake cooling, the ring fairing is missing on the launch car.

Although details around the front end will change, the wheels are typically a design chosen to last for the whole season. This year the McLaren Enkei wheels sport a novel set of drillings to aid brake cooling. The usual spokes formed into the wheel between the hub and the rim, stop short and a radial set of holes are made near the rim. Although not present of the launch car, there will be a dish shaped fairing added to small pegs formed into the wheel to aid the airflow out of the wheel.

The high rectangular inlet and large undercut set the car apart from the "U" pods of the 2011

In 2011 McLaren were not afraid to try a radical sidepod set up, This was the “U” shaped sidepod, with the angled inlet shape creating channel in the upper section of sidepod (About the MP4-26 “U” shaped sidepods).  This year the team have adopted more typical sidepod format, with high\wide sidepod inlets and steep undercut beneath. I got to ask Tim Goss about this:

ScarbsF1: Can you tell us about why the concept’s changed, why you don’t feel that was a benefit this year?
Tim Goss: Last year’s U-shaped side-pod worked very well with what we were trying to achieve last year with the exhaust layout, it was all intended at creating more down wash to the rear end, and it performed particularly well last year. This year at a fairly early stage we set about a different approach to both the external and the internal aerodynamics of the car, and then once the exhaust regulations started to become a little bit clearer then it was quite obvious to us that the U-shaped side-pod no longer fitted in with both the internal aerodynamics and some of the external aerodynamics that we pursued early on. So it works, it worked very well last year, but it’s actually just not suited to what we’re trying to achieve this year.”

.

Not extreme like the "U" pod, but the sidepod tops do incline slightly

In frontal profile the high and wide cooling inlet is obvious.  The team have been able to incline the sidepod tops slightly, this isnt quite a “U”pod shape, but is quite distinctive.  At the rear the team have kept the sidepods narrow and slimmed the coke bottle shape in tightly to make the sidepod join the gearbox fairing creating a continuous line of bodywork to the very tail of the car.

the heated air from the radiators passes up over the engine and out of the central tail funnel

As well as the external airflow considerations, McLaren looked the sidepods internal airflow, they wanted a cooling exit on the cars centreline. This would have been compromised with the “U” sidepod, so the more conventional shape was selected. The cooling arrangement is similar to Red Bulls philosophy, the radiators direct their heated airflow upwards and around the engine, this then exits in a tail funnel. The launch car had quite a modest central outlet, but we can expect to see far larger versions used at hot races.

the front upper section of sidepod is switchable for version with cooling outlets

Aiding the tail funnel there are also cooling panels on the upper leading edge of the sidepod, either side of the cockpit padding and various panels arund the rear of the coke bottle shape. Different panels will be used depending the cooling and\or drag demands of the of the track.

Last years more complex roll hoop cooling inlets have been simplified into one below the engine inlet

Other cooling functions are covered by the inlet below the roll hoop. Last years double inlet set up has gone and now a single duct is used. This probably cools both the gearbox and KERS.

Viewed through the rear wing the exhaust bulge is obvious

The other notable aspect of the sidepods are the exhaust bulges. These stick out prominently on the flank of each sidepod. They don’t serve an aerodynamic function themselves, but simply fair-in the final 10cm of exhaust pipe. This final section of exhaust is now strictly controlled by the regulations. Its position must sit within specific area, it must point upwards between 10 – 30 degrees and can point sideways plus or minus ten degrees. McLaren have fixed the exhaust in the lowest most rearwards position possible, the tail pipe then pointing steeply upwards and inwards. From the limited view it would appear to direct the exhaust plume towards the outer span of the rear wing.

This would make a blown rear wing (BRW), the added flow from the exhaust aiding the wing in creating downforce at lower speeds. The exhaust position and fairing also suggests an alternative exhaust tailpipe could be used. Paddy Lowe confirmed that different solutions would be tried in testing. From overhead its clear to see the exhaust could be angled differently to blow over the rear brake ducts fairings to create downforce directly at the wheel.

The gearbox case design is not the shrunken design we saw with Williams in 2011 , the differential is low but not unduly so. The top of the case sitting neatly under the tail funnel. Pull rod suspension remains at the rear of the car, while conventional pushrod is on the front end. Lowe commented that the Lotus brake antidive system was not specifically looked at, but was part ”of a family of solutions” that has been looked at in the past. The engineers feeling that the Lotus system was illegal and hence had not been explored further. They declined to comment of the possibility of an interlinked suspension system.
Behind the gearcase, the rear impact structure is mounted midway between the beam wing and floor, fully exposing both the beam wing and allowing airflow into the central boat tail shape of the diffuser. As the diffuser was covered up, its not clear if there are features to drive airflow into the starter motor hole. A new feature on the beam wing is an upswept centre section, the extra angle of attack in the middle 15cm of the wing having a slot to help keep the airflow attached. The upper rear wing is a new design albeit similar the short chord DRS flap wing, we saw introduced at Suzuka last year. The DRS pod is still mounted atop the rear main plane and its hydraulics fed to it through the rear wing endplates. The flaps junction with the endplates follows recent McLaren practice with a complex set of vents aimed at reducing drag inducing wing tip vortices.
Not much else in terms of structures or mechanical parts were evident at the launch. Lowe did confirm to me that the Mercedes AMG KERS remained packaged under the fuel tank in one assembly. Also adding that there would not be an significant weight loss to the system.  As a significant reduction in weight was made between the 2009 and 2011 season, via the consolidation of the Batteries and Power Electronics into one unit.

Mp3 of the MP4-27 Engine fire up via McLaren

Mercedes AMG: Engine Build Challenge

During my visit to Mercedes AMG before Christmas, the company set us a challenge that’s been put to other more notable visitors. In the engine build area, two engines were arranged in each bay, but without the coil pack, heat shield and exhausts fitted. Our task was to fit these parts to one side of the engine, along with tightening each fastener to the correct torque setting. A dozen journalists attended the day, the challenge being made even greater as the two current Mercedes AMG drivers had also previously completed the challenge.

The coil pack is handed over and the challenge starts...

The first job was to fit the coil pack. The four-pronged carbonfibre cased unit is a press fit atop each spark plug, then the we needed to connect CAN electronics interface near the front of the airbox.

Next the heatshield goes on... (eventual challenge winner watching intently behind)

A small reflective coated carbonfibre heatshield goes over the coil pack, attached with three small bolts, one of which is smaller and requires a different torque setting.

Access to the 24 exhaust studs under the engine was surprisingly good

Then onto the exhaust system, weighing about 3kg each exhaust is hand made from thin sections of inconnel welded together. Although the 4-into-1 exhaust is one assembly, there is some play in the primary pipes joints with the collector, so fitting the four exhaust pipes to the studs on the engine requires a little fiddling. Each exhaust pipe bolts to the exhaust port with three nuts, two above and to the side of the exhaust pipe, and one centrally below.

A blur of hand movement gets each nut threaded on...

Each of these 24 nuts being tightened to the same torque setting. With the engine up on the stand and being able to kneel below the engine, getting access to each fastener was surprisingly easy, none of the exhaust pipes being particularly obstructive. I’m sure doing the same job with the engine in the car and the floor fitted is a very different story.

A quick check that each nut is torqued correctly and the job's done.

I completed the challenge in 4m 30s and I was satisfied I’d done a good job. However ex Racecar Engineering magazine editor, Charles Armstrong Wilson completed the challenge in an impressive 3m 30s! Even though one (un-named) journalist took as long a 7m 57s, as group us journalists were confident we’d done a good job. But the teams Drivers had soundly beaten us all. Nico Rosberg did the challenge in 3m 15s, while Michael Schumacher did it thee minutes dead!

The job of the F1 engine builder and mechanic is a difficult and skilled one, the skills of the F1 driver are ever impressive and I’ll stick to drawing racecars and not working on them!

Mercedes AMG: KERS development

One of Max Mosley’s lasting legacies in F1 was the introduction of his vision of a green initiative in F1. As a result KERS (Kinetic Energy Recovery System) was introduced 2009, as part of a greater package of rule changes to change the face of F1.
KERS is a system which harvests energy under braking and stores it to provide the driver with an extra power boost each lap. A simple technical summary of KERS is here (http://scarbsf1.wordpress.com/2010/10/20/kers-anatomy/ ).
During the 2009 season McLaren were applauded for running Mercedes KERS at every race and it was widely reported as the best KERS in use that year. Along with a few other journalists, I was invited along to Mercedes AMG Powertrains in Brixworth, UK to hear about KERS development since 2009. With Managing Director Thomas Fuhr and Engineering Director Andy Cowell giving a presentation on the range of work Mercedes AMG does with its F1 teams.

Mercedes AMG Powertrains reside on the site that was previously Mercedes Benz High Performance Engines (MBHPE). Now renamed to reflect the wider application of the groups knowledge, both to uses outside F1 and to areas other than engines. Powertrain is a catch all term covering; engine, transmission, electronics and of course KERS Hybrid systems.
The company have built a purpose designed Technology Centre on the site, which historically was the Ilmor engine plant and positioned just a few miles from Cosworth in Northampton. Clearly this area has a rich seam of Engine knowledge.
Formed around three buildings the entire F1 engine and KERS development is carried out on site, only specialist functions such as the casting of the crankcases is carried out off site. Additionally other Mercedes AMG work is carried out here, such as the AMG E-cell car.

KERS 2009
Mercedes AMG (MBHPE as it was known then) developed their first KERS for 2009 in house. At the time McLaren were the primary customer for the system, although Force India and at the last minute Brawn GP were also customer teams that year.  Force India had a chassis prepared to run KERS, but chose not to during the season.  Brawn had a chassis designed before their switch to Mercedes engines, so their car was not designed to accept the Mercedes KERS.

Mercedes AMG: 2009 Battery pack and water cooling radiator

In designing the system, Mercedes AMG had a specific requirement from McLaren. As the effectiveness of KERS was unknown, McLaren didn’t want to compromise the car if KERS was removed. So the system was packaged to fit into a largely conventional car. Whereas other KERS suppliers went for a battery position under the fuel tank, McLaren and Mercedes AMG placed theirs in the right hand sidepod. Low down and far forward, on the floor between the radiator and the side impact structures. The battery pack contains not only the array of individual cells, but also the pump and pipe work for its water cooling circuit. As well as the electronic interfaces for its control and monitoring. The assembly is around 7cm high, 12cm wide and 40cm long. The KBP is probably the single heaviest KERS component. In 2009 this sidepod package was acceptable as the teams were still on Bridgestone tyres and seeking an extremely forward weight distribution. Thus the 5cm higher mounting in the sidepod was offset by its forward placement.

2009 KERS and the batteries sidepod location relative to the engine

Conversely the smaller Power Control Unit (PCU) was placed in a similar location in the other sidepod, ironically the PCU is around the size and shape of road car battery. This left the monocoque uncompromised, aside from the smaller cut out for the MGU in the rear bulkhead.

The 2009 Zytek developed MGU

Then the Motor Generator Unit (MGU) is mounted to the front of the engine.  This device generates and creates the power for the KERS. Its driven from a small set of gears mounted to the front of the crankshaft.  the unit remains with the engien when the car is dismantled and is oil cooled along with the engine.

All of the components are linked both to the SECUs CAN bus and to each other by High Current Cable. The latter taking the DC current between the Batteries and MGU. With this packaging Mercedes AMG quotes the total system weight as 27kg.
Designed and developed by Mercedes AMG, but other partners were involved; the unique battery cells were supplied via A123 and the MGU was partnered with Zytek. Although the power control electronics were solely a Mercedes AMG in house development.
Through the 2009 season both McLaren drivers had a safe and reliable KERS at each race. The system was safe even after crashes and was fault free despite rain soaked races. Safety was designed in from the outset, all electrics were double insulated. Teams can also measure damage to the unit via accelerometers and insulation sensors, so any impact or incidental damage can be monitored and the car retired if the need arises. Additionally each cell in the battery has its temperature monitored. KERS batteries are sensitive to high and low temperatures, each cell needing to operate in a specific thermal window. Too low and the unit is inefficient and too hot and there’s the danger of explosion.
Perhaps the only criticism was the sidepod battery mounting, despite several incidents, this never put any one in danger, so this never proved to be an unsafe installation.

KERS 2011

2011_Mercedes_AMG_engine

For a variety of non technical reasons KERS was agreed not to be raced from 2010 until the planned 2013 rules. However this plan changed, but not before Mercedes AMG had made new strategic plans around KERS.
Mercedes AMG set out a longer term strategy to work on research for KERS in preparation for 2013, as well as working with AMG to develop the road car based E-cell technology.
(Link Mercedes AMG E-Cell chassis  )
This changed when the plans for the 2013 engine were pushed back to 2014 and KERS was agreed to be reintroduced for 2011. Thus the 2013 development plans had to rebased and deliver a refined version of the 2009 KERS for 2011. Moreover there were now three teams to be supplied with KERS. There was no Christmas for Mercedes AMG staff 2010!
As a result of the research work carried out after 2009, Mercedes AMG now solely design, develop and produce the entire KERS package, aside from the Battery cells. So now the MGU is a wholly Mercedes AMG part.

The MGU fits to the front of the engine and driven from a small set of gears

With KERS effectiveness proven in 2009, it was possible to have the cars designed around it, rather than it be an optional fitment. So the packaging was revised and the entire system integrated into just two units. The MGU remains attached to the front of the engine, still driven off a spur gear on the nose of the crankshaft. While the KBP and PCU are now integrated into a much smaller single package and fitted under the fuel tank. The unit bolts up inside a moulded recess under the monocoque, the unit being attached using four vibration mounts, and then a closing panel and the cars floor\plank are fitted under it.

The 2009 battery pack (yellow) is now integrated with the power electronics (not shown) in a single unit under the fuel tank (red).

It’s this integration of the batteries and power electronics that has has really slimmed the 2011 system down. Mercedes AMG now quote 24kg the entire KERS, much of the 3kg weight loss being down to the reduction in the heavy power cabling between these units.
Not only is the packaging better, but the systems life and efficiency is too. Round trip efficiency stands at a stated 80%, which is the amount of power reapplied to the engine via the MGU after it has been harvested and stored. Improvements in efficiency being in both the charge and discharge phases.
Battery pack life was extended to as much as 10,000km, several times the 2009 predictions that batteries would need replacing every two races (2,400km). Over this period, the cells do not tend to degrade, as the team manage the unit’s condition (‘State of Charge’ & temperature) throughout the GP weekend to maintain their operational efficiency.
The 80hp boost KERS provides, stresses the engine. This was well known back in 2009, but for 2011 along with DRS the car can be several hundred revs higher than the usual EOS (end of straight) revs. Mercedes AMG quoted 15-25% more stress for a KERS and DRS aided lap, this needing to be taken into account when the team monitor the engines duty cycle, thus deciding when to replace it. Mercedes conducted additional dyno development of the engine being kept on the rev limiter to fully understand and counter this problem. This work paid benefits; Hamilton ran many laps at Monza bouncing off the rev limiter along the main straight, while chasing Vettel.

KERS in use
Although the max 60KW (~80hp) output can be reduced from the steering wheel, its normal for the driver to use the full 80hp boost each time they engage the KERS boost. With a reliable KERS, the driver will use the full 6s boost on every lap. Media reports suggest Red Bulls iteration of the Renault KERS does not use this full 60kw. Instead something like 44kw, providing less of a boost, but allowing smaller batteries to be used. The loss in boost being offset by the overall benefit in car packaging.
The driver engages a KERS boost either via a paddle or button on the steering wheel, or by the throttle pedal. The latter idea being a 2009 BMW Sauber development, where the driver pushes the pedal beyond its usual maximum travel to engage KERS. Nick Heidfeld brought this idea to Renault in 2011 and the over-extended pedal idea has also been used for DRS too.
Once the driver is no longer traction limited out of a turn, they can engage KERS. Usually a few small 1-2s boosts out of critical turns provides the ideal lap time. It’s the driver who has to control the duration of the boost, by whichever control. As with gear shift the drivers can be uncannily accurate in their apportioning of the boost around the lap. It’s suggested that the 2009 Ferrari system apportioned the duration of the KERS boost via a GPS map, the driver simply presses the button and the electronics gives them the predetermined amount of boost. This solution came as surprise to Andy Cowell, so one wonders if this is legal or perhaps if the report is true.
From on board shots, we’ve seen the steering wheel has an array of LEDs or numerical displays to show the driver the boost remaining for that lap. The SECU will have control code written to prevent overuse of KERS around a lap.
Typically the battery will hold more charge than a laps worth of harvesting\discharge. So that any unexpected incidents do not leave the driver without their 6s of boost.
In use KERS can be used in several different ways. When lapping alone KERS typically gains 0.45s per lap, although this varies slightly by track. Along with DRS is can boost top speed by 12kmh. As explained the driver uses a pre-agreed amount of boost, decided from simulation work done at the factory before the race. So the planned strategy of KERS usage will be used in practice, qualifying and in parts of the race. However in the race the driver can use KERS tactically to gain an advantage. Drivers are able to use more a KERS boost to either overtake or defend a position. One feature of 2011 along with the Pirelli tyres being in different condition during the race, was the driver’s freedom to alter their racing line and use their grip and KERS to tackle their rivals.

KERS future
KERS continues in its current guise for another two years, then for 2014 along with all new engine regulations there will be a new format KERS. Energy recovery will be from different sources, so the overriding term for the hybrid technology on the car will simply be ERS (Energy Recovery Systems). However KERS will still exist, harvesting energy from braking, but will have a greater allowance for energy stored and reapplied. But, there will also be TERS (Thermal Energy Recovery), which a MGU harvesting energy from the turbocharger. Overall ERS will provide a third of the engines power for some 30s of the lap. No longer will the driver press a button for their KERS boost, it will be integrated in their demand for power from the throttle pedal. The electronics will be constantly managing the Powertrains energy, harvesting and applying energy based on whether the driver is on or off the throttle. In 2014 Powertrains and ERS is set to become very complicated.

First analysis: Caterham CT-01

Now entering their third year what was Team Lotus and now Caterham F1 have produced their most contemporary package yet. Also in the second year of their partner ship with Red Bull and Renault for the supply of their power train, there will be inevitable comparisons of the CT-01 to the cars from its technical partners. Indeed superficially the car bears some resemblances to the RB7, but the car is indeed the work of the technical team lead by Mike Gascoyne and Mark Smith in Hingham. Where as Red Bull supply the Gearbox\Hydraulics and Renault the Engine\KERS package.

Although the rendering of the car is clearly wearing 2011 spec wings, vanes and brake ducts, its evident the car is another step forward in design terms for the team.

Three features stand out as different from the 2011 T128; the nose, the sidepods and the roll hoop.

Firstly the nose (Cutting from this months F1Racing magazine) is the first example we have seen of the revised 2012 nose regulations, limiting the front of the nose to a height of just 55cm. However the remaining raised monocoque section between that and the cockpit can be 62.5cm high, so we see the step between these two sections and this is partly softened by the ridged “V” nose. (more detail on the 2012 nose rules)

The sidepods follow the Red Bull template with slim sidepods tapering out at their base. The coke bottle shape streamlines smoothly into the gearbox fairing, there being no cooling outlet from the sidepods themselves, instead the tail funnel acts as the main outlets, while there also appears to be small outlets either side of the cockpit sides.

Amidships we see the all-carbon blade type roll structure from 2011 has disappeared, replaced by a more conventional roll hoop. With part of its structure exposed in the form of the struts supporting the roll structure. Its likely this structure has some metal in its construction. The use of heavier metal in the structure, is offset by the shape being more structurally efficient and probably of equal weight compared to the all carbon blade.

The nose cone is much wider and shallower than in 2011, this being create enough mass within the deformable structure while still meeting the “V” shaped front bulkhead. A new front wing is in development, its likely this will follow the 2011 trend for an endplate-less design with a three element wing meeting the centre section in a curled profile. The raised front section of chassis means Caterham have retained their steeply include front suspension. Interestingly, the bulges on the nose, seem to a reverse twin keel and mount the front leg of the upper wishbone. Around the cockpit opening their appear to be cooling outlets, these aiding cooling allowing much slimmer sidepods. The bodywork aft of this area bulges outwards slightly and sweeps back smoothly around the engine to the tail funnel. In meeting the 2012 regulations the exhausts are tucked in quite low and inboard. The mandatory last 100mm of exhaust being covered by fairings formed into the engine cover. From these pictures its hard to tell how steeply the exhausts are angled at. Therefore its hard to tell if the exhaust effect the flow under the rear wing.

As the sidepods are so slim and there being no low level exhausts, there is a wide expanse of exposed floor. The diffuser sweeps outwards and there is a generous cut out around the rear wheels. The centre section of the diffuser often termed the boat tail is exposed to the airflow. Suggesting the rear impact structure is raised clear fo the floor. This is in contrast to Red Bulls preferred practice of a low rear crash structure. The lowered section probably allows airflow over the floor to pass through the starter motor hole to aid airflow passing up under the diffuser.
By using the Red Bull Carbon fibre gear case, the rear suspension is also largely taken from the Red Bull. Thus it employs pull rod operation for the springs and dampers. However the KERS installation may follow either Red Bulls Pannier style battery installation or the more typical under-fuel-tank installation.