Name: このロケット動力車は音の壁を破るために設計されています (This Rocket-Powered Car Is Engineered to Break the Sound Barrier)
Uploaded: 2021-01-14T10:37:18.000Z
Duration: 8 min 22 s
Description: VoiceTubeの動画で発音を聞きながら英語表現を覚えよう！学べる英語：

You're watching a test run of one of the fastest cars ever made.

Zipping across the South African desert at 628 miles per hour, this car is the result

of over a decade of extreme engineering and aerodynamic modeling.

All with the end goal of breaking the world land speed record.

But the team behind this project wants to go even further.

They want to reach speeds nearing 1,000 mph, aiming to be the fastest car in the world.

The land speed record is all about taking a manned vehicle across the surface of the

Of course, it's not as simple as it sounds.

Regulated by the International Automobile Federation, this competition has some ground

Basically, you have to have a car that's controlled by a human onboard.

The vehicle must have at least four wheels which are in contact with the ground.

And it's your average speed over a measured mile that you do in two opposite directions

within the space of an hour that gets you your land speed record.

The current record holder is the Thrust Supersonic Car, or Thrust SSC.

Back in 1997, it plowed across the Black Rock Desert in Nevada at 763 miles per hour, breaking

both the sound barrier and the world record.

Now, Ben and this team have engineered a next generation supersonic car– Bloodhound.

It's designed to go speeds north of 800 miles per hour, with a stretch goal of a whopping

A lot of the team's benchmarks are written in miles, so we'll be using this conversion

box so the metric system is never too far away.

One of the things that makes Bloodhound an incredibly complex, arguably one of the most

complex vehicles ever to be designed aerodynamically is the fact that we're traveling at supersonic

speeds, but over the surface of the earth.

From an engineering point of view, that's an incredibly complex problem.

As a travelling object approaches the speed of sound, it starts to catch up to its own

soundwaves-- compressing the air in front of it.

Once it goes faster than those waves can be created, it generates areas of extremely high

pressure called shock waves -- along with a deafening sonic boom.

Today, we have military aircraft that can handle these shockwaves and travel at supersonic

speeds with ease, but for a car– it's a little bit more challenging.

Whereas supersonic aircraft have the luxury of generating these shock waves and then the

shock waves propagate out into this effectively infinite space around them, a car by definition

One: How do you keep the car on the ground?

The shock waves that get underneath the car will interact with the ground plane and actually

We want a car that's not going to generate so much lift that it could take off the ground.

The second part of the challenge is all about drag minimization.

When those shock waves form, they generate a lot of drag.

How do we keep the resistive forces as low as possible so that we've got sufficient thrust

And as if those two challenges weren't difficult enough,

The strength of the shockwaves that we're going to be generating are higher than any

vehicle travelled over the surface of the earth before.

So managing those extremely strong shock waves, at those kind of speeds, is really the key

aerodynamic challenge that we're trying to overcome.

To optimize the car's shape for these conditions, the team looked to Computational Fluid Dynamics.

Essentially what CFD is, is virtual wind tunnel testing.

Now, behind me here, we've got a real physical wind tunnel.

This circulates air round at high speed and passes that airflow over a body that you can

then measure forces, pressure distributions and so on.

In CFD, we do all of that, but in the virtual world, inside a large supercomputer.

The way it works essentially is we go back to the fundamental governing equations of

high speed aerodynamic flows and those are the Navier Stokes equations.

It turns out that they are very, very difficult equations to solve directly.

And so we need large high performance computers.

Once the team nailed down the optimal shape for Bloodhound, the next hurdle was figuring

The design of the wheels was a massive challenge.

They rotate at 10,000 rpm and the forces at the rims of those wheels is extraordinary.

To prevent the wheels from literally tearing themselves apart under those forces, the team

had them forged out of an aircraft-grade aluminium alloy.

As you'd imagine, it's nothing like what you'd see under the hood of an ordinary

We've actually taken a modern military jet engine that's operating in the Eurofighter

And that's kind of the main thrust source that we've been using.

To take the newly built Bloodhound out for a spin, the team packed up shop and took a

The Hakskeenpan is an incredible place to run a straight line racing car like Bloodhound.

We've prepared 19 kilometers of track by about three kilometers wide.

We actually clear the stones off the track

to make what is now the world's best straight line racing track.

From October to November of 2019, the car went through various speed tests, hitting

450, 550 and eventually 600 miles per hour, the final goal for this round.

I was about 300 meters to the side of the track and it is an incredible thing to witness.

The first thing you experience is the noise of the cars.

You hear the jet engine at this point, it's over the horizon.

And what is incredible is seeing this white speck, and then within seconds, it's 300 meters

away from you. It is an incredible thing to witness.

I've been working on Bloodhound for over a decade and over that decade it's been very

It's been pictures and plots on a computer screen.

So to be there in South Africa and see this vehicle in real life, it felt like you were

With this year's testing now complete, there's mountains of data to sift through and engineering

improvements to be made before their attempt at a world record.

During the high speed test program, the car was heavily instrumented with sensors measuring

pretty much everything you could think of measuring on a car like this.

What we're now doing is mapping those measurements back to the CFD model that was used to design

the car in the first place to see how well that CFD model corresponds with how the car

That will help us define the size of some winglets, which we might need to add onto