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There are few things in life as thrilling a live Formula one race. The speed and roar
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of the engines sends adrenaline pumping through yours veins, but this isn't just mere entertainment.
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Racing at the highest level tests engineers and drivers in ways that normal production
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cars do not and forces them to think of clever and innovative ways to improve performance.
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These technologies have on multiple occasions found their way into our everyday lives. There
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are countless examples of this happening since the birth of competitive racing.
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The first reliable steel disk brake was produced for the Jaguar C-Type in 1953. The exposed
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disk brake allows the brake to shed the heat generated in breaking much more effectively
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than the drum brake and allows stopping distances to decrease. This technology helped the Jaguar
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C-Type to reduce wear on the break and reduce braking distances,allowing it to take 3 of
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the 4 top places in the 1953 24 Hour Le Mans and has since saved thousands of lives in
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the real world, due to their superior braking and reliability. Over the course of the 24
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hour race many of their competitors had to drop out of the race because their brakes
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were disintegrating. The improved breaks also meant that the drivers could break much later
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into a turn and thus post much quicker laps.
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Racing technologies are always a few steps ahead of production cars, but these technologies
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generally trickle down over time as costs reduce. Carbon fibre is probably going to
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be the next great innovation in car manufacturing. All F1 cars use carbon reinforced composite
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brake disks which save weight and are capable of operating at higher temperatures than steel
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disks, but you will rarely see such high end materials in normal everyday cars. The material
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was first used in the monocoque of F1 cars in 1981 when McLaren unveiled the MP4/1. The
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material had been used for small parts previously, but some engineers doubted it's ability
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to withstand a crash. That all changed when John Watson crashed his McLaren at the Monza
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Grand Prix and came away uninjured. John Watson himself doubts that he would have been so
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lucky if he had been driving in a traditional aluminium frame.
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After that day the other racing teams were playing catch up and now every F1 car uses
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the material. Carbon fibre has slowly found it's way from high-end racing cars to production
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cars thanks to car manufacturers like BMW who have made huge investments in manufacturing.
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Carbon fibre production has typically been incredibly expensive due to the vast energy
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required but BMW invested invest 300 million into a hydro-powered carbon fibre manufacturing
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plant in Moses Lake, Washington with the aim to produce 9000 tonnes of the material per
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year exclusively for their cars. This increase in production quantity reduced the prices
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enough to make it viable for production cars like the BMW i3 and i8, which have an all
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carbon fibre reinforced plastic frame (wrong word). Carbon fibre is becoming more and more
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common and we can expect to see it gradually replacing metal parts in our transport because
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it reduces weight and thus reduces energy consumption, while also being incredibly strong.
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It has even found it's way into our passenger planes with the Boeing 787 dreamliner and
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Airbus A350 XWB being primarily made from composite materials, but more on that in my
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next video.
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These examples go on and on but today we are going to focus on the leaps in our understanding
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of automotive aerodynamics as a result of competitive racing. Some of the most talented
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aerodynamicists in the world work for modern day F1 teams and the lessons they learned
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through racing has helped improve the efficiency of our cars immensely. Allowing them to cut
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through the air effortlessly, drive faster and use less fuel, but it wasn't always
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this way. In the early days of competitive racing there
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wasn't really any distinction between race cars and street cars, they only discernible
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difference was in the lunatics that were to driving them. The distance between the left
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and right wheels were narrow and the centre of gravity of the cars were high, making the
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cars incredible unstable in turns and susceptible to roll overs....
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Early sports racing cars were typically light weight front engined vehicles and their designers
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understood the basic concept of drag. The engines at their disposal were relatively
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low powered and inefficient and so to counteract this they made their cars as round and streamlined
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as possible to reduce the effects of drag. Drag is defined by this equation:
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Where Rho, which is the greek letter that looks like a p represents the density of the
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fluid the object is moving through, v is the velocity, C is the coefficient of drag which
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is a property defined by the shape of the object and A is the cross sectional area of
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the object.
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You can see from this equation, that the drag force increases dramatically as the speed
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of the car increases because the velocity is squared. That is why to gain even a tiny
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bit of speed at the higher levels of racing huge amounts of additional horsepower are
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required. This is why these early designers focused so much on lowering the drag for their
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low horsepower vehicles. The coefficient of drag for a circle is just 0.47, while a square
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is 1.05. So by rounding a shape we can reduce the drag by more than half. And if we decrease
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cross-sectional area by half we can reduce the drag by half again. So it's clear why
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the shape effects the performance of the car so much.
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This equation is useful for understanding how drag works, but the designers were not
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getting a full picture of what was happening to the air around their cars, because they
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had essentially just designed aerofoils that were capable of producing lift. At best this
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reduced the car's ability to transfer power from the tires to the ground at worst it made
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the car begin to lift off the ground and crash. .
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One of the first people to realize and attempt to correct this problem was a young Swiss
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engineer and driver called Michael May. He recognised the potential of using an aerofoil
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to create negative lift and thus push the car down towards the ground, thereby improving
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traction, grip and handling of his car. So he modified his Porsche Type 550 by mounting
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this huge inverted wing over the cockpit. The wing proved so successful that it beat
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all other Porches in it's first race in 1956 at the Nürburgring 1000 Kilometre race,
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this drew criticism from the Porsche's factory team and they pressured the race organizers
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to ban the wing on the grounds that it blocked the view of the drivers behind him. This incident
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stalled the development of downforce generation, but the idea was too good to go unnoticed
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for too long.
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In 1963 Jim Hall mounted an adjustable wing onto his Le Mans winning Chaparral 2E. He
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understood that downforce was essential to keep his car glued to the road, but also recognised
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that it added drag. So he made this wing controllable, this way it could be made horizontal to reduce
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drag on long straight sections of the track and lowered when entering turns.This was the
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first of it's kind and the idea was quickly adopted by Formula 1 teams, but these high
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mounted movable wings were poorly engineered and after a series of breakages they were
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banned completely. But the automotive world had hit a tipping point. The idea could no
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longer be ignored and manufacturers began to design entire cars around this concept
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rather than just going for the most aerodynamic shape possible.
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There is no better example of this than the evolution of the Porsche in the late 60s.
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Porsche has made a name for itself as a giant killer with it's sleek, low drag roadsters
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that were managing to beat much more powerful Ferraris and Maseratis, but as the company
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grew Porsche decided to design a new high horsepower racing engine and build an innovative
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body around it and thus the iconic Porsche 917 was born.
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It's birth was not without it's share of difficulties. Early on it was plagued with
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aerodynamic instability. This new formula of high power and low drag was a new concept
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to Porsche and it took them some time to perfect it, but they gradually reprofiled the body
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work and the 917 began to dominate races in the early 70s.
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This progression hit a boiling point with the accidental discovery of ground effect
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with the Lotus Type 78. During the development of the Type 78 the head engineer Peter Wright
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and his team were experimenting with prototypes of a new design for aerofoil sidepods in the
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Imperial College London wind tunnel. Over the course of the day the rudimentary prototype
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wings began to sag towards the ground of the wind tunnel and to the amazement of the team
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there was a huge increase in downforce. Initially they didn't understand what was causing
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the increase, but soon discovered that by adding cardboard skirts to the sidepods air
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was being forced and trapped beneath the car and as we have discussed in previous videos,
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when air is forced through a constriction it experiences an increase in speed and a
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decrease in pressure. This is called the Venturi Effect. They later developed these brush skirts
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that sealed the air under the car, which were later replaced with rubber skirts.
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This low pressure air relative to the high pressure air flowing over the car caused a
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huge increase in downforce with only a marginal increase in drag, making the car stick to
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road in corners and reach incredible speeds on the straights. This was the holy grail
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of aerodynamic discovers and all Formula One cars since have followed this design principle.
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The Lotus Type 78 set the standard for what we see today. The successor to the Type 78,
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the Type 79 was so dominant that teams like Brabham had to think of even better ways of
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achieving that ground effect phenomenon. The Brabham BT46, is probably one of the most
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controversial cars to ever hit an F1 track. Teams were struggling to keep up with the
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Type 79 and Brabham's team led by Gordon Murray were trying to figure out ways of beating
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it. Gordon Murray was reading through the rulebooks when he noticed a loop hole. The
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rules stated that cars with moveable devices that were primarily used for aerodynamic advantages
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were not allowed, but he realised that if he could make an argument for a new device
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being used primary for cooling then they could use a fan that sucked air from the bottom
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of the car and ran it through the engine. The energy of this system would primarily
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be used to cool the engine, but it had the added bonus of sucking the car onto the road.
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The Brabham BT46 and Lotus Type 79 faced off in the 1978 Swedish Grand Prix and despite
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complaints from Colin Chapman, the founder of lotus, the fan car still ran. Mario Andretti,
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driving for Lotus took an early lead, but the Brabham driven by Niki Lauda was gradually
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gaining and eventually overtook Andretti on the outside. Niki Lauda and the Brabham BT46
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went on to win the race by 34 seconds, but this would be the fan cars first and final
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competitive race. Other drivers complained that the car was firing rocks and dusts out
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the back and despite the car being within the regulations the other teams pressured
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the FIA to outlaw the car. Brabham were told they could run the car for the rest of the
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season, but instead decided to withdraw, leaving the door open for Lotus to win the 1978 Formula
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One season. The following year Lotus slipped to fourth place as other teams caught up with
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ground effect technology. I think this exemplifies why I enjoy racing, for me it's less about
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the drivers and more about the engineers behind them competing to create the best vehicle
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possible within the rules.
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Today engineers have a huge amount of tools at their disposal to rapidly prototype new
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car bodies. I mentioned that the Type 78 was tested in a wind tunnel and that testing helped
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towards the discovery of ground effects, but prototypes are time consuming to make and
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wind tunnels aren't always available to everyone. One of the biggest developments
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in F1 and engineering in general in the past 2 decades has been the advancement of computer
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aided engineering. With this method we can simply generate a huge variety of models and
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test all of them in a short space of time to quickly figure out which design is best.
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The animations you are seeing on screen right now are actual engineering simulations that
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accurately depict the airflow over an F1 car. I have teamed up with SimScale an online based
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engineering simulation software to bring you more of these animations in future. With this
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kind of power in an engineer's hands progress can happen so much quicker and that's lucky
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because the regulations in F1 are constantly changing and challenging the design
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teams behind the cars.