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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.
コツ:単語をクリックしてすぐ意味を調べられます!

読み込み中…

The Greatest Innovations In Formula One

217 タグ追加 保存
Ntiana 2018 年 5 月 15 日 に公開
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