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