Saturday 22 February 2014

Aerodynamics in 2014 - The Year of the Penis Nose

Nose


What the ****?


Yes, they have done it again. The FIA have shot themselves in the foot.

Back in 2012 you may recall 'stepped noses'. In an effort to increase driver safety and probably aesthetics, the FIA rule makers reduced the maximum height forward of the front bulkhead (basically the nose in front of the wheels). With the teams wanting to continue to maximise the airflow under the car, their ingenious idea was to create a very ugly 'step' in order to bring the front of the nose down to the required height. This was certainly a fail from the FIA not considering how there rules would be interpreted.

This year the FIA thought they would go a step further, and now state the tip of the nose must be no higher than 185mm from the reference plane (floor of the car). The nose must also be no higher than an imaginary diagonal line drawn from the front bulkhead (where the drivers feet are) to the front of the nose.

Unfortunately this backfired again, as the FIA dictated the chassis height to only reduce by 100mm. Que teams again to take back their advantage with weird solutions.

The penis shaped protrusion of the Torro Rosso


In order to meet the low nose point required many teams have adopted a penis shaped protrusion to satisfy the regulations. While some became accustomed to the stepped noses, these phallic extensions are pretty horrific. Even Anne Summers tweeted 

“So it looks like Toro Rosso have taken inspiration from our sex toy collections #collaborationopportunity”, 

Possibly the worst interpretation was the 'twin tusk' design of the Lotus. The release pictures showed a monstrosity of large tusk like protrusions extended from the front of the car with one tusk longer than the other. This stems from the FIA ruling stating the tip of the nose 'has a single, cross sectional area of 9000m2'.
The unsightly 'twin tusk' of the Lotus E22

Take a note of the word single there, which is what Lotus have done with one single protrusion meeting the regulation requirements. These protrusions re-inforce the wing pillars to form a crash structure and act to direct airflow, but are quite thick which could offset this advantage.

Teams such as Ferrari, and in a more graceful fashion with the best looking car of 2014 Mercedes, have abadoned the penis extension and gone with a more conventional design. This is even more so on the Ferrari, with a very low 'vacuum' cleaner nose. Some may argue that the Ferrari nose is actually worse.

The 'vacuum nose' Ferrari
These teams may not be exploring the grey areas of the nose design enough to retain the advantage of maximum air flow under the car.

So what actual performance gains come from the shape of the nose? As discussed the aim of the game is to get as much air flow under the nose as possible to allow the underbody aerodynamics and diffuser to work to their full potential. This is why we have had very high noses in recent years. However, although visually striking the shape of the nose does not carry equally striking performance gains. Ferrari James Allison, who worked on the Lotus tusk nose before joining Ferrari this year stated on the different concepts  "There is not that much in it - they are just good to talk about because they are right up at the front of the car."

In a year of ugly horrors Mercedes still produce another great looking car



Ban on Exhaust Blowing
Exhaust gas being directed around the diffuser

What really carried a massive advantage in recent years was exhaust blowing. Back in 2010, Redbull experimented with blowing hot exhaust gasses around the rear diffuser, a device at the back of the car which generates huge downforce and grip. The hot gasses coming out of the exhaust almost created an invisible barrier to keep air flowing through the diffuser affectively. The hot gasses also created pressure change which sucked more air through the diffuser. The result was a big increase in grip when the driver hit the throttle pedal coming out of corners. Redbull designer Adrian Newey knew he was onto a winner and and the aerodynamics of the Redbull were built around this concept to get maximum advantage, which led to the team's dominance.

Note the location of the exhaust exit
However when the driver came of the throttle pedal to brake, where downforce is important, the advantage dissapeared as there was no hot exhaust gas available. To stop this engine manufacturers programmed their engines to make the engine burn fuel even when the driver was off the throttle. The advantage became so big that cars where now overfilling their tanks with heavy fuel loads.

By 2011 every team was at it, and the designs becoming more advanced and hugely affective. I remember attending Silverstone that year, just as the FIA announced a ban on this technology only to get slapped back into place by teams complaining over lost performance. What I didn't really hear on television became much more apparent on track. The engines sounded like a low thudding machine gun when the cars braked for the corner and an acrid smell entered my nostrils. The video below gives you a good idea of the sound you for some reason never heard well through your television:


                                      


For the following season, the FIA stipulated the exhaust exit on the car had to be placed high up upon the sidepods rather than next to the diffuser. However teams as ever employed methods to get around this. With a small indent on the exhaust exit to direct exhaust gas down, using the 'co-anda' affect exhaust blowing was still, if a much more diminshed, important generator of downforce on the cars.

However for 2014 we now see the exhaust located in a central position ahead of the diffuser, making it impossible to direct exhaust gas towards the diffuser. "There will be a lot less downforce as there will be no [exhaust] blowing" stated Jenson Button before testing.  "I don't care what they say, there is still a massive amount of blowing on an F1 (2013) car."
Exhaust exit location for 2014

This change will mean a big reduction in downforce, and with the torquey turbo engines making wheel spin easier you will be seeing a lot of cars going sideways when exiting slow corners. Great!

Wing Changes

In an effort to reduce more downforce from the new cars the FIA and have made changes to the front and rear wing rules

In an effort to reduce punctures, the front wing has been shortened from 1800mm to 1650mm. As the front wing generates a vast amount of downforce on the car this will have a big impact. This also makes it harder for the front wing to direct air around the outside of the tyre. Teams will try a claw a small advantage back with now being able to direct airflow in between the car and the tyres.

The virtual box that the rear wing has to sit in stipulated by the FIA is now 20mm smaller. There is also the removal of the beam wing. Smaller area means less downforce. However in an effort to claw more downforce back McLaren has an innotive solution of shaping the rear suspension into an aerodynamically detailed 'blocker'. This blocks airflow travelling around the coke bottle rear bodywork of the car heading towards the diffuser. A pressure difference speeds up airflow under the car creating more downforce. This may give McLaren quite a big advantage in 2014 and is hard to copy due to the need of other components to work in harmony.

The new Mclaren's innotive 'blockers'

All these changes combined equal significant downforce loss. But ask any experienced F1 geek and he will tell you these losses will be clawed back in a year or two with new innovative concepts...












Sunday 9 February 2014

2014 F1 Engines Explained

Its here.

Tag Me!
                                                                       

2014 is upon us and with it some of the biggest changes to Formula One cars for a generation! With phallic shaped nose cones causing a stir there is also another controversial change to the formula. Its out with the V8 engines of last year and in with smaller and greener high tech turbo-charged V6 engines.

Turbo

A view of the turbo at the back of the new Mercedes power plant
                            
Some of you might be asking - what exactly is a turbo? Less complicated than you think, a turbo is simply a device which uses pressure from what would be wasted exhaust gases exiting the engine to spin a turbine, which connected to a fan via shaft sucks more air to the engine generating more power. As you are making more power from what is waste, a turbo engine is a more efficient engine than a naturally aspirated (that means non turbo) engine. At the moment, with all the talk and worry of global warming car manufacturers are moving away from big engines to smaller, efficient turbos charged engines to reduce emissions. As modern Formula 1 has rich and powerful car manufacturers as investors, its no surprise they have steered the rules towards the new greener ethos of road cars.


You may now be thinking that turbos are perfect, right? There are a few downsides. The first is there are more moving parts in an engine generating huge pressure and heat. This means turbo engines can often break. To make them more reliable for every day use, road car manufacturers limit their turbos to produce a lot less power than they potentially can. In F1, where every fraction of a second counts, every team will be pushing their more complicated turbo engine to the limit. This means we will see what has become a rare site -more cars breaking down .

Secondly, from a drivers perspective turbo engines have less 'driveability'. The way the torque - the actual force of the engine - comes into play when a driver puts his foot down can feel delayed and, with big power, almost violently catch you unawares. You will have probably heard of 'turbo-lag' before. This was famously noticeable in 80's and 90's high performance turbo road cars, where you put your foot down hard and for a second or more and... nothing happened. Then all of a sudden the turbo spools into life and it feels like you are being propelled by a space rocket! This made those cars of old with quick 0-60 times ever more impressive, as a second or more was wasted with you not really going anywhere. This is because the turbo needs time for exhaust pressure to build to get it going. Modern road cars have fancy methods involving electronics and crafted turbos to make this delay pretty much unnoticeable, but it can not be completely hidden in powerful turbo engines. This why a lot of petrol heads and super car manufacturers like Ferrari and Lamborghini prefer the linear and normal power delivery of a normal naturally aspirated engine to a turbo. Non turbo engines are more predictable, its easier to judge your right foot as the power builds smoothly. 

Thirdly and finally turbos themselves are quite heavy and require the help of an intercooler to cool down all that compressed air coming into the engine. Although you have an efficient engine producing power from waste, there is still added bulky weight and cooling is much more important. These factors are hugely significant in F1 cars. Although the 2014 turbo engines are smaller and so is the fuel tank, the extra cooling requirements and bulky turbo (and other new engine bits for 2014 discussed later) will mean packaging the car behind the driver and keeping the weight down is a challenge for the teams. 

Ask an F1 geek about the turbo cars of the 80's and you will almost certainly get a positive reaction. The main reason behind this is ridiculous horsepower.
This was often over 10 times as powerful as your average family saloon car at around half the weight. Coupled with no traction control to help with wheel spin and little aerodynamic grip compared to today these legendary cars were a beast to tame and unreliable. Spiralling costs and scary speeds saw them banned in favour of naturally aspirated 3.5 litre engines.

This year the turbos are back, but in a very different format. The BMW M12 turbo engine in the back of the Brabham and Benneton cars of 1987 in qualifying trim, with tiddly 1.5 litre engines, produced approximately 1400 horse power.  This years 1.6 litre engines will be producing less than half of that - just over 600hp and around 760hp for 33 seconds of the lap with the new ERS system. 

So why are this years cars a lot less powerful if they are practically the same size? The main reasons are efficiency and reliability. In 1987 for example Brabham could run their monster BMW engine to 1400hp - but only for a few laps in qualifying. And even after a few laps it was not unusual for gearboxes and even the engines themselves to shatter into pieces.
Turbo engines of the 80's were notoriously unreliable
The immense pressures travelling through the engine could end in an explosion showering bits of piston, valves and connecting rods all over the race track.

Rather than just one race session, the new engines are designed to cover a lot more mileage. In fact, you can only change the engine a maximum of 5 times in the 19 race long season. Also, you can only change the turbo, electronics, energy store, and 2 parts of the ERS (described in the next section) 5 times a season or you will face the same penalty.

Rev Limit and Displacement

One of the most controversial changes to the engine is the reduction in RPM, or revs per minute and the reduction in displacement (pretty much the size of the engine). The distinct violent whining buzz of an F1 engine comes from is super ability to spin the crankshaft of its engine at insane speeds. Last years engines were limited to 18,000rpm but this year this limit is 15,000 rpm. Coupled with the reduction in size and the removal of 2 cylinders, the engines are noticeably quieter.

This is certainly a sour point for fans. My lasting memories of going to see Formula One races in the V10 and V8 era are of me approaching a the track from a distance hearing the violent thunderous aggression of an F1 engine getting louder and louder. Especially in the V10 era the sound would often vibrate advertisement boards and bridges. It was awesome.

Now we have news after Jerez testing of team managers being on mobile phones in the pit lane- something they were unable to do before because of the noise. It leaves me quiet worried but I am not going to make a full judgement until I hear them in person. The only added bonus is the sound of the turbo and the new energy recovery system whirring off throttle. Listen for yourself:



Energy Recovery System



Introduced in 2009 'KERs' took energy from braking and stored it as electrical energy that could be released when the driver required it for for just under 7 seconds a lap. Similarly for 2014, what is now 'MGU-K' (motor generator unit -kinetic) also takes energy created from braking through the power train, and stores this in the 'ES' (energy store) to be used as a boost when needed. However there is more wasted energy available to be harvested through the 'MGU-H' (motor generator - heat). This is an electrical generator connected to the turbine shaft of the turbo. When the car is braking and the turbo is not needed the turbine of the turbo will be freewheeling, but this would be wasted energy is harvested through the MGU-H and stored in the 'ES' (energy store) to be used when needed. This energy can be used as a boost, or instead used to spin the turbo up when power is required greatly reducing turbo lag. Also the MGU-H can be used to control the speed of the turbo turbines to reduce pressure if necessary acting in place of a waste gate.

In total the MGU-K can fire back a total boost of 4 mega joules per lap through the engine crankshaft giving around 160hp for 33 seconds. This is 10 times more energy than last years KERs which means failure of this system will be hugely detrimental to performance. Unlike last year were KERs was operated by a 'boost' button on the steering wheel, the 33 seconds of boost from the MGU-K will be pre-programmed into the car to boost automatically at set points over the lap. This can still be adjusted by the driver by changing to different engine maps on his steering wheel. Teams will have to calculate when that all important power boost will be needed.

Fuel

This years engines will produce similar power levels to last year during parts of the lap, yet will be over 30% more fuel efficient. This years formula is a fuel limited formula, in that engines are limited to 100kg of fuel per race. This year the emerging road car technology direct injection will make its F1 debut allowed in the new regulations. This allows fuel to be sprayed directly into the cylinders of the engine, rather than mixed with air through and intake valve. The result is more precise fueling and therefore increased efficiency.

Gearbox

Finally, another big change this year is the requirement for 8 speed gear boxes with set ratios for the whole season. On a track with long fast track such as Monza you want long gear ratios meaning higher top speed at the sacrifice of acceleration. But on a short slow track such as Monaco you want short ratios for quick acceleration out of slow corners at the sacrifice of top speed. While teams changed the ratios race to race now they do not have this luxury. A balanced ratio will be needed to give them and best performance for all the races in the season.