25 little-known facts: A thread of things you probably don't know!

1:
The differently-coloured tip at the front of a commercial jet engine is frequently rubber, and a de-icing measure: It distorts under even slight asymmetric load, throwing off ice before it forms big clumps. The sharpest object in the universe…

Electrolytically etch a necked tungsten needle in potassium hydroxide and the interaction between geometry & electric field strength creates a tapered tungsten nanoneedle.

These have been made to taper down to the atomic level.

When nuclear reactors are too blasé and you want to bend physics to your will…

Why not cool a reactor core with a fluid compressed & heated to such extremes that it's no longer a liquid or a gas but something else entirely.

It's the Supercritical Water Reactor thread! Most reactors in operation today are light water reactors, and there are good reasons for that: Water is both moderator & coolant, they have safe negative reactivity coefficients and decently high power density.

However they are complex and limited by temperature & efficiency.

Nuclear power: Is it the future or outmoded technology? Let's take a look at five Generation IV designs and maybe take some inspiration.

Which is your favourite?

A nuclear rabbit hole for your weekend… What we're building right now are Generation III pressurised water or boiling water reactors. They're sturdy and mature, if a tad expensive.

The GenIV reactor designs share some features: Passive safety, simplified architecture, less waste and (hopefully) lower costs.

Let's learn about a technology that saved billions of lives and enabled the modern world!

And let's learn about the darkness in the soul of one man.

Beyond Good & Evil? You be the judge.

The Haber-Bosch process…

Be warned: By the end of this thread you will need to stand in judgement of a man and decide for yourself whether he was a saint or a monster.

You might even owe your life to him. That makes it tricky.

But first, we shall start at the beginning…

In January 1930, with the Great Depression strangling the world, a 22 year old Frank Whittle patented the turbojet.

The patent lapsed in 1934 when he couldn’t afford the £5 renewal, but by then the world was changing.

The story of the jet engine, in a single thread… Something new…

The Whittle engine comprised two axial compressor stages and a centrifugal compressor, powered by a turbine following the combustor. 

The use of a centrifugal compressor would become a key differentiator. Other turbojets favoured axial compression.

What is Supercritical CO2?

You're about to learn of a technology that will change the world and how we generate energy.

It's not quite a liquid and not quite a gas, but it's all Miracle!

Get ready: We're going deep on this one… Earlier this year, the SwRI in San Antonio generated electricity from a closed cycle supercritical CO2 powerplant. Why is this important?

Because it's a super high efficiency technology that cleans & miniaturizes the thermal heat engines we use to power… Everything.

A mote in the eye of God.

This is the Noor concentrated solar plant in Morocco, a 500 MW beast of focused solar fury, with 7 hours of energy storage.

But what are the pros & cons of this temperamental technology?

And what is its future? Read on… We're not talking about photovoltaics, the creation of current in semiconductor layers. No, concentrated solar is more dramatic, and has unique abilities.

It's a steam turbine generator, powered by concentrated rays. But how do we concentrate them? There are many methods…

Don't look up!

On April 13th, 2029, a 300 metre, 27 million ton asteroid called Apophis will hurtle past our planet, closer than GPS satellites.

Near miss!

But if one day The Big One comes and it's aimed right at us, how do we save ourselves?

The asteroid intercept thread! On the 26th September, 2022, NASA gave it a try: The 500kg DART spacecraft did a 6.6km/s head on collision with the asteroid Dimorphos, a 170m long, 5 million-ton loosely aggregated asteroid, orbiting a much larger twin.

It worked! But what other methods are there?

What do road & rail maps tell us about political culture? 

Why are you being stealthily robbed, every day of your life, if you live outside the capital in most countries?

How can new roads short-circuit this, and bring prosperity?

A transport nerd thread!

Here are the motorway maps of several European countries. What do you notice in each?

A web of development branching out from the capital like a fungus. It brings fertile economic soil, but subtly distorts all our lives.

All that glitters is not gold.

Sometimes it's something even better! From weird foods through engineering marvels to tiny things that would kill you if they got the chance…

…what are the most valuable substances on Earth?

Let's get stuck in! First, the cheap seats for comparison:

Steel ranges from $1 per kg (mild steel) to $150 (Hastelloy B2) and more grades get added regularly.
Aluminium is close to $1/kg.
Titanium is $20, largely due to energy costs in production

Now for the rich boys…

https://x.com/Jordan_W_Taylor/status/1794055530501099622?t=OGxjpHt36vGPMzhpM8izEQ&s=19

38 years ago near Pripyat, Ukraine, reactor 4 of the Chernobyl nuclear power plant exploded.

What happened?

This thread goes into the unique RBMK reactor and the design features that contributed to the calamity.

And how, in modern plants, this risk has been eliminated… The RBMK-1000 is a huge cylindrical channel reactor, with an 11.8m diameter, 7m high core. 1,700 tons of graphite is arranged in packed blocks with channels for fuel & control rods. There are 1,661 fuel channels, 211 control channels, and 192 tons of Uranium fuel.

It's a beast!

Aircraft are thirsty and burn lots of fuel, right?

Wrong.

The average fuel efficiency of air travel today is about 67 mpg per passenger. That makes it more fuel efficient than your drive to work. The best hit 100mpg/passenger.

How did aviation manage it?

A thread. It wasn't always so. The venerable 707, doyenne of the 60s jet set, was more than twice as wasteful: Its fuel consumption per hour was 50% greater than a modern 787-8, even though the 787 is 50% heavier, flies 50% further and carries a hundred more passengers. 

How?

In Sheffield, Britain, the Translational Energy Research Centre has imported a rare beast from America.

It's called a molten carbonate fuel cell, and it could mean the ability to generate clean, zero carbon energy…

…from coal.

A thread about saving the world? We are installing a dizzying array of clean power solutions worldwide right now, but..

…it's also a world with 2,500 coal power plants in operation, releasing 10 billion tons of CO2 a year.

All our work is for nothing if we can't retrofit these.

We need something special.

Is Europe even relevant anymore? -Or is it only good for Harry Potter, the Louvre and fancy cheese? 

Let's take a whimsical jaunt through things that Europe still does quite well…

And where it might stand to improve.

Our continent has a bit of an inferiority complex these days (except that one country, you know who you are!), but as we browse a US app on a phone made in China, you may reflect that we still know how to do a few things well.

Sometimes things that you'd never think about…

You may not realise it, but the next few years are going to be great years for experimental aircraft and aerodynamics innovation.

Let's take a look at a few of the highlights you should know about… As early as this year we may see flight testing of the Airbus eXtra Performance Wing: This revolutionary wing senses air disturbance and constantly morphs to optimize performance and quell turbulence.

A semi-aeroelastic hinged wingtip also allows a super-high aspect ratio.

A fighter emerges, bloody and bruised, and he's not giving up: King Coal is back in the ring!

In this new world of clean power there is a presence we dare not speak of, but it's back with new technology and new tricks.

It's the Coal Power Thread! In power generation worldwide coal remains king, with over 1/3 of all electricity generated from thermal coal, emitting over 10 billion tons of CO2 a year.

This is Drax, in Yorkshire, which burned 36,000T of coal a day at it's peak, yet is half the size of the biggest plants!

Hydrofoils!

The fastest boats on the ocean: No Bond villain should be without one.

How do they work? How does the ship not fall over? Let's find out…

The hydrofoil thread. A displacement hull floats freely from the hydrostatic pressure of displaced water… but it takes a lot to push a hull through water.

Water is a 830 times denser and 50 times more viscous than air: So why not mount wings, go fast & “fly” the hull into the air?

The hydrofoil.

Molten Salt Reactors: The bonus thread!

In our last thread we detailed the liquid fueled molten salt Thorium reactor, which is basically nuclear energy on Hard Mode.

Now for some simpler entry points into the technology… which is your favourite? Concept 1: The Advanced High Temperature Reactor

The AHTR is a large (1.5GW) molten salt cooled reactor with a solid graphite matrix fuel assembly exporting high process heat through a helium heat exchanger.

Creating the infinite energy machine: A thread on the Molten Salt Fast Reactor!

Specifically, the liquid fuel variant, where the nuclear fuel is dissolved in a liquid coolant and flows continuously at over 700C.

Why on earth would you build such a beast??

Let's find out… The MSR is a mixture of lithium & beryllium fluoride salts with low enrichment U233 or U235 fuel dissolved in the coolant. Moderators & shape factor in the reactor governs where chain reactions and cooling are occurring.

The coolant is over 700 Celsius but only about 1 bar.

Jesus turned water into wine. We can turn water into fuel.

But will divine intervention let us fly to the Canaries guilt-free? In this thread we go deep on the pros, cons and challenges…

Let's talk hydrogen fuelled flight… So what is the case for hydrogen?

It’s clean, can be produced from water via electrolysis or thermal cracking and can be burnt much like kerosene, but with zero carbon emissions. it also has a specific energy (MJ/kg) 3 times higher than kerosene. So a no brainer?

Not quite.

Happy Sunday! Here's a thread of four very different articles for your reading pleasure, covering:

>Chaos theory, hurling & storms.
>Why innovation is driven by a million strivers, not a few great men.
>Love & the 737: Why aviation will always be with us.
>A short sci-fi story. Aviation, love, life and the quintessential air taxi: Why we need to keep making the world smaller.

https://x.com/Jordan_W_Taylor/status/1797252229155492345?t=gKBTLUy0s86MJlhBOjOaOQ&s=19