Tag Archives: tech highlights

Tech Highlights: Mercedes rear suspension tweaks

As part of a number of changes under the skin of the car to address the issues they faced last year, Mercedes have added an extension to the rear upright where the upper wishbone joins (here’s an image of it). In my analysis of the Mercedes W09 for Race Fans I mistakenly wrote that the rear upper wishbone design raises the rear roll centre. I must’ve messed up my sketches, as the raised position actually lowers the rear roll centre.

Lowering the rear roll centre loads up the rear tyre upon steering input, producing better traction and overall grip amongst other benefits. As with any of these things there are pros and cons of doing this but I won’t delve into them in too much detail here. This post mainly explores how Mercedes have achieved a lower rear roll centre.

If you don’t know about roll centres and other suspension related terms then I’ve got a blog post on it here.

IMG_2596

The above sketch shows how the roll centre (RC) is influenced by the angle and position of the upper and lower wishbones (apologies for the terrible image quality, if you’d like to buy a poor student a new iPhone then please let me know). RC1 is the reference suspension geometry, drawn in pencil.

RC2 (blue lines) depicts the effects of the raised upper wishbone Mercedes are utilising. As you can see the substantial height increase from the upright extension slightly lowers the RC compared to RC1.

RC3 (black lines) shows that the angle of the wishbones has a much greater influence on the RC, as the upper wishbone is kept in the same position at the upright but its angle to the horizontal has increased. In this case RC3 is higher than both RC1 and RC2.

The wishbone angle and position is limited by aerodynamic idealisations, keeping the mass of the car as low as possible and regulations. They all sort of play off eachother too, adding to the complication.

The teams often encase the lower wishbone and drive shafts into one aerodynamic fairing, preventing the effects of shaft rotation in freestream air from effecting the performance of the diffuser immediately behind (Google ‘Magnus effect’ for more on this). This limits the height at which the lower wishbone sits, so adjustments to the RC can only be achieved through the upper wishbone alignment and the centre of gravity (CoG). Lowering the RC can be done by angling the top wishbone upwards, but then the air would not pass perpendicularly over the entire structure and the inboard bodywork would have to be raised to cover it. This would be detrimental to the airflow over the car and also induce unwanted lift (i.e. increased drag). Aerodynamics govern the majority of the car’s performance, so we are therefore left with raising the upper wishbone to achieve the desired lower RC.

Lowering the CoG is also critical to car performance. The gearbox hosts the rear suspension mounts: machined aluminium clevises that transfer load through to, in most cases, a carbon case. With strength often comes added weight, so ideally the wishbones should be mounted as low as possible while achieving the designed suspension characteristics. It is for this reason that we have seen the likes of Williams’s impressively low gearbox case in 2011.

Finally, the location of the single exhaust exit is regulated and limits what can be done with the upper wishbone’s position. The exhaust passes over the mounting point of the trailing arm of the wishbone, but with the mounting point so high Mercedes have had to weld in a bridged section to the pipe to do so. Both aerodynamics and CoG play roles here too, as the mass of the pipe should be kept as low as possible while controlling the exhaust plume’s position and interaction with the surrounding surfaces.

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Tech Highlights: Top aero features of 2017

As Formula 1 introduced a raft of changes ahead of the new season, 2017 was always likely to produce some new features on the aerodynamic front. Here are some of the key highlights from this year.

T-wings

The appearance of T-wings on this year’s cars is a consequence of the changing of the rear wing dimensions for 2017. During the rewriting of the rules a small region that was previously occupied by the outgoing higher rear wings was accidently left unattended. The extruded 50 x 750 mm area was instantly taken advantage of by the teams, with the majority of them converging on some form of twin element design by mid-season.

w08_twing

Mercedes were one of the first teams to debut a T-wing in 2017

Continue reading

2015 US GP Tech Highlights

In all honesty I didn’t expect to be writing this piece at all, but thankfully the teams provided us this week! Even though we are heading into the latter stages of the season, and despite the distance between Europe – where all of the teams are based – and the US, the developments keep on coming through. Most of the paddock will be looking ahead to 2016 and the upgrades seen in Texas provide a few clues to what we could see next year.

However with no proper dry running (aside from the latter stages of the race, which wasn’t exactly bone dry) it would have been difficult to evaluate the these components, so expect those who brought developments to fully utilise any dry running in Mexico this weekend. Continue reading

2015 Russian GP Tech Highlights

Been crazy busy at university at the moment so unfortunately – whilst I tried to find time to write this exclusively for my blog – I’ve had to copy most of it over from my analysis piece I did for Richland F1. Quick update on YouTube things: very close to getting more videos out… 🙂

The Sochi circuit in Russia is a track of compromise – one of the longest straights on the year kicks the lap off, whilst the high speed S2 and technical final sector make for an aerodynamic headache. This sort of layout shows who has really done their homework and provides us the best chance of seeing the most efficient cars.

With not many more ideal opportunities to introduce new developments to the cars in 2015, Russia saw a number of various upgrades ranging from McLaren’s further revised power unit to an interesting tweak to the Mercedes front wing. Continue reading

2015 Japanese GP Tech Highlights

After the barrage of upgrades that appeared in Singapore, the Japanese GP weekend was a relatively quiet one for developments. Aside from Force India applying the finishing touches to its B-spec VJM08, the only major update came from Mercedes who had, incidently, not brought anything to Singapore a week ago.

So – not much to talk about in this week’s Tech Highlights but we can go into some detail about the Mercedes and Toro Rosso tweaks. Continue reading

2013 Brazilian GP Tech Highlights

After a long, hard year of maximising the current regulations, this final edition of the 2013 Tech Highlights still has plenty of things to look at, including some items that will carry over into next season. Despite the fact that the teams will have put over 80% of their resources into the 2014 car some months ago, the technical side of the sport never ceases and it is for this reason why I love writing on this blog so much. There are always things to talk about and I hope you enjoy this final post in this section until March next year.

Lotus

Introduced at the USA GP last weekend, the E21 featured metal machined tyre squirt slots ahead of the rear tyres which have been carried over for this weekend. The slots reduce the effect of the turbulence, generated by the sidewalls of the tyre, impinging on the diffuser to further increase the efficiency of the underfloor aerodynamics. This is done by bleeding airflow from above the floor through the slots, projecting into the turbulent area and offsetting this “squirting” effect.

Lotus slots

These slots are machined from metal rather than carbon fibre. Mercedes also have slots produced from the same process. This is unlike Red Bull and Ferrari, with their slots made out of carbon fibre. I understand that the only feasible reason for the difference in material is to reduce warping, created by the heat of the exhaust gases that head directly next to this region of the floor. Although there is a fence guiding the gases to their eventual location, it does not fully prevent the slots getting heated. Metal is more heat resistant than carbon fibre and therefore seems a more reliable choice.

Red Bull

With Pirelli bringing their 2014 prototype tyre this weekend, the teams chose to bring various pitot tube arrays to gather data on how the new tyre characteristics change the airflow structures of the car under loading. Unfortunately, the wet weather denied the teams of an opportunity to test next year’s medium compound slick tyre, so the tubes had to be packed away again. Except for Red Bull…

During the early parts of FP1, Mark Webber’s RB9 was armed with an array behind the left front tyre, measuring the airflow being projected off of the tyre and suspension members. This was possibly a calibration run as there did not appear to be anything new on the front wing that would prompt a measurement test.

Later in FP1 and during FP2, Sebastian Vettel’s car was equipped with another array, this time located behind the rear left tyre and also behind the diffuser. After initial installation tests on intermediate tyres, the team elected to go out on the 2014 prototype slick, despite the damp conditions. The purpose of this experiment was to gather as much information about the aerodynamic flow structures on the new tyre to help develop for next year. However, with the wet conditions, Vettel was unable to push and put much loading through the tyre, making their findings almost irrelevant.

They may get some idea of airflow structures under simple circumstances, such as the loading of the tyre at speed along the straight. The car is designed to go round corners, so perhaps this was a failed exercise for the Milton Keynes squad. Ross Brawn, responding to comments made about the tests carried out by Red Bull, said: “Sometimes taking no measurements is better than gathering false or distorted information”.

Aside from the tyre testing I found it interesting to hear that the team deliberately asked the FIA to do a front wing load test on three front wings for this weekend. The wings were identical and the same as the ones brought the last round in the USA. In terms of structure, however, they may well have been made up differently. Perhaps they were trialing a new carbon layup for next season. More flexi-wing antics in 2014?

Rear brake sensors, wired through the top wishbone, were also mounted on Vettel’s RB9 to gather more data on the braking characteristics of the car. This will be essential next season as the more powerful 2014 ERS (Energy Recovery System) will have a greater influence on the braking of the car in comparison to the current KERS unit. Such is the power that teams will be allowed a control device, monitored by the ECU, to smooth the braking phase, as the system harvests energy much more aggressively. More on this in a future 2014 post.

McLaren

Also hoping for some 2014 tyre running was McLaren. On Thursday a picture was taken of this sensor attached to the front wing endplate. These are not thermal imaging, infrared sensors however. I am unsure of what they are designed to measure although it could be sidewall deflection. Having said that, the sensor appears to be facing directly towards the face of the tyre, if not more to the inside shoulder.

Mercedes

A new piece of information that has to come to light since last weekend is the introduction of new Brembo calipers on Lewis Hamilton’s W04. Hamilton has made it clear that one of his main struggles with the Mercedes car is its different braking characteristics compared to the previous McLarens he has driven. Unlike Mercedes, McLaren use Akebono (or Carbon Industries) calipers and discs. According to Hamilton, the Brembo combination does not give the initial bite that he desires. Paddy Lowe’s switch from McLaren to Mercedes mid-season may well have influenced this change.

2013 United States GP Tech Highlights

Once again, few and far between updates on the cars this weekend as the season is very quickly drawing to a close. However with Ferrari and Lotus still firmly in the hunt for second place in the Constructors’ championship, both teams have been forced into making some changes to the cars for this weekend to keep in touch with Mercedes.

Ferrari

Ferrari have slightly updated the front wing cascade on its F138, creating a total of three elements at the endplate of the device instead of two elements previously.

Ferrari FW cascade

An additional element here will produce a slightly different vortex, aimed at guiding airflow around the front tyre to more critical components downstream such as the leading edge of the floor and the bargeboards.

The team were also re-evaluating their new sidepod airflow conditioner introduced in Abu Dhabi although it was never raced. This was coupled with a strake at the base of the vane that replaced the r-vane introduced in Japan.

The fact that Ferrari keep changing this area of the car on a regular basis is quite concerning as this is a relatively sensitive region of the car. It works in conjunction with the edge of the floor and the Y250 vortex produced off the main plane of the front wing, guiding vortices that help seal the airflow beneath the car that travels on into the diffuser. In this video posted on SomersF1, we can see the large vortices that are directed by this component – http://www.somersf1.blogspot.co.uk/2013/11/austin-gp-video-compilation-of-vortices.html

The team have been changing this area quite a lot lately so perhaps their aerodynamic issues lie at the rear of the car. They have certainly been struggling with traction lately although I am unsure if this area of the car can be related to such problems.

Also new on the car this weekend was an interesting modification to the outer walls of the diffuser (see the image of it here – http://2.bp.blogspot.com/-vx-nSelktu0/UoYDbfrPzVI/AAAAAAAAIlU/Dmk8XOqnW4M/s640/diffusore+ferrari+2.jpg). Confusingly, the modification appeared to be exactly the same shape and specification as the last version only that it was a rapid prototype of it rather than finished carbon fibre. It was as if the carbon fibre outer wall had been cut off and replaced with the rapid prototype with some sort of filler to blend the two together.

Perhaps there were some minute differences, such as the angle of the projection of the wall, but nothing major had been changed. They would certainly have the facilities to quickly produce something like that at their factory and send it over within a day, or even at the circuit itself.

Finally, the team chose to replace an updated beam wing seen in Abu Dhabi to a more conventional, straight layout for this weekend.

Lotus

Introduced on Kimi Raikkonen’s car in Abu Dhabi, Lotus were pursuing their latest iteration of their rear wing endplates in free practice, taking it forward to qualifying and the race for this first time this weekend. They are composed of 7 strakes hanging beneath the endplate, compared to three, thicker elements from the previous design.

Lotus RW endplates

These strakes are designed to work in conjunction with the airflow coming off of the brake ducts upstream and with the outer wall of the diffuser below. Each strake points outwards slightly, aiding the outwash and upwash of the diffuser below.

Both cars ran the long wheelbase this weekend, confirming that the team clearly see a gain with this configuration rather than just a preference between the two drivers as Heikki Kovalainen was brought in to replace Kimi Raikkonen, who is undergoing back surgery.

A second, smaller bulge – behind the large “pelican beak” – beneath the nose also appeared on the E21.

Red Bull

If you have Google Chrome (or just copy and paste into a translator) I would thoroughly recommend reading this article – http://www.omnicorse.it/magazine/32639/f1-gp-austin-tecnica-la-red-bull-con-i-cerchi-trattati-con-il-polysil-e

It would appear as if Red Bull have added a heat sink – in the form of a silicone coating from Polysil – to the rims of the RB9, aiming to transmit more heat from the brake/hub assembly inside of the front tyres. Perhaps this radiates the heat directly onto the sidewalls of the tyre which would help during the tyre warming phase.

With fluctuating track conditions at the Circuit of Americas during qualifying, Red Bull were one of the only teams to produce consistent laptimes. This could have been aided by generating heat more quickly into the tyre using this method.

It could also be used as a way of managing the turbulence created by the tyre immediately behind as the heat could change the characteristics of the passing airflow.