There's a lot of thread content on this page, so this is a pinned index of engineering threads for easy navigation. Some mine, some not.
1) The HP turbine blade, single crystal casting and "metallurgy's secret cheat code":
1/This is a thread about metallurgy's secret cheat code, and how it's used by the aerospace industry to accomplish things that no material should.
In particular, how that cheat code is enabled on the humble, but amazing, jet engine turbine blade.
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.
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.
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…
It's named after titans.
It's our favourite space age material, used in rockets, planes & medical implants.
It brings us the colour white.
It's an absolute devil to make.
This thread is the story of Titanium.
In 2022, short on electrical grid inertia and long on renewable power, Ireland installed the world's largest flywheel, 130 spinning tons.
Why did we do something so preposterous?
And are there other, better storage technologies? Let's find out.
It's the grid storage thread!
When 460 knots just isn't fast enough...
We've been cruising the globe at basically the same speed since the 1960s. Faster would be nicer, so what are the challenges facing hypersonic airliners?
Read on...
By the artifice of Man and God is born a furnace that forges the future.
This is the big nuclear reactor thread!
A beginner's guide to the main reactor types, with lots of diagrams...
A spark in the darkness...
This week Sheffield Forgemasters achieved, in 24 hours, the welding of a nuclear Small Modular Reactor RPV mockup that should have taken up to a year.
How?
Incoming energy revolution: This is the Electron Beam Welding thread!
Our friend, the high temperature aero gas turbine blade. It's coated, film cooled, made of single crystal Nickel superalloy, generates 1000HP and pulls thousands of g in an environment hundreds of degrees higher than its melting point.
And eventually it may be obsolete...
You can't squeeze blood from a stone...
But with 1000 bar of water pressure, you can shatter shale with the fists of Poseidon, and squeeze out precious, precious methane.
This is The Fracking Thread!
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.
We all know the SR-71 Blackbird: The American cold war super-spyplane. It was based on the Lockheed A-12 design, which won a competition against Convair in 1959 to produce the iconic aircraft.
But the A-12 was just the 12th design iteration. There were others.
Read on...
1/This is a thread about metallurgy's secret cheat code, and how it's used by the aerospace industry to accomplish things that no material should.
In particular, how that cheat code is enabled on the humble, but amazing, jet engine turbine blade.
The future of speed?
Yesterday the 220 knot Airbus RACER took to the skies for the first time: A high-tech compound helicopter.
But what are compound helicopters, why did work on them stop for three decades, and will the Racer bring them back?
A thread.
Touching the void.
The glider that almost became a spaceship, how to surf the polar vortex and one man's extraordinary vision to fly higher than anyone...
...Without an engine.
The Perlan project, a thread.
Things that sound simple & aren't: The bearing and oil system on a jet engine.
First, the main bearing locations on a Trent 1000 engine.
Bearings need oil, oil gets hot. Oil needs circulating and sealing.
Next, the seals...
This is Ascension island, and this little mid-Atlantic volcanic island might well have the key to our future survival on this planet.
For, you see, this island's ecosystem is artificial: Ascension island was terraformed.
Read on...
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 desalination thread!
This is the Ras Al Khair desalination plant in Saudi Arabia. One of the world's largest, it outputs over 1 million cubic metres of water a day.
But how is desalination done?
Get ready for lots of head-melting schematics...
High on a mountain in the Atacama desert, Chile, the European Southern Observatory is building something immense.
It's called the Extremely Large Telescope, and here's a highlight reel of this beast's ultimate capabilities.
Fun facts: A 1GW nuclear plant, supplying about 1 million people, will make about 3 cubic metres of vitrified high level nuclear waste a year. Fast reactors can make even less.
A similarly sized coal plant will output 300,000 tons of ash and over 6 million tons of CO2 annually.
Invented in Britain! Used… somewhere else?
A short, tongue-in-cheek thread about my mother country's amazing ability to put in all the groundwork and then go “...nah.”
Can you think of more examples?
Read on…
Additive Manufacture for heat exchangers!
Using a Gyroid structure, a complex 3 dimensional interconnecting lattice inspired by nature, low pressure heat exchangers have been made that are 50% more effective than counterflow heat exchangers, but at only 1/10 the size.
It's niche thread time!
Which future high efficiency aircraft configuration is best? (Place your bets!)
Happily, in 2020 ONERA & DLR ran a study on this very question. This is a summary.
With all the buzz about
#LK99
and the possibility of a room temperature superconductor, let's have a topical thread.
Can a superconducting induction coil make the perfect battery?
And is it world changing? Read on...
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…
This is the Airbus BLADE laminar flow wing demonstrator, which flew in 2017. It showcases a technology that can reduce wing skin friction by 50% and fuel burn by 8%.
But among it's hazards are tiny insects. Why?
This is a thread about design inertia, and how small decisions can lock a company into an approach that runs for decades, even if it's different from everyone else.
Can you guess what it is yet?
1/On the 4th November 2010, while climbing over Indonesia, Qantas flight QF32 reported a problem on their Airbus A380, the world’s largest passenger aircraft.
Engine 2 had just exploded.
This thread runs through it all, and how a tiny 0.5mm manufacturing defect was the cause.
A heart so hot it pumps molten lead...
Let's dive into lead cooled fast reactors!
Not literally, but let's find out what makes them tick, what challenges remain, and why the unreal prospect of cooling reactor cores with hot lead could be a Very Good Idea.
A thread.
Why are aircraft the shape that they are?
Basic aerodynamic stability: A primer.
I've no catchy tagine for this thread: It's all about the basics. Here we go...
How do you create Nothing at all? And once you've created Nothing, how do you measure it?
It's a lot harder than you think…
Creating the domain of gods: This is the vacuum system thread!
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…
A heart of helium: A power source that could save the world?
This is a thread about the meltdown-proof, hot as hell, Very High Temperature Reactor, and something called the Dragon.
Let's turn up the heat…
Speaking of chocolate…
The Danes, who scarcely need weight loss drugs, loosed Ozempic on an unready world, and the miracle drug is such a hit that it saved Denmark from recession last year all on its own and is growing their GDP just as it shrinks everyone else's waistlines.
In high vacuum the mean free path for air molecules gets so large that normal aerodynamics breaks down.
Shown is the path of air molecules through a turbomolecular pump in high vacuum, at extreme RPM.
Tomorrow we'll go even further, in the Vacuum System thread!
Aerospace.
From airliners through helicopters to gas turbines & powerplants, Europe is a peer with the US in this industry, leagues ahead of the rest of the world, and has an R&D pipeline stocked with wonders. 275 billion Euro a year and a million employees in Europe alone.
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!
This dark December we all need a ray of light.
How about a ray of 10 billion suns, prizing apart the secrets of metallurgy, cellular genetics and drug discovery?
A thread on the Diamond Light Source.
Ultra low-budget aerodynamics 1:
Use a van with a splitter plate instead of a wind tunnel!
The Airbus AlbatrossONE demonstrator showing Semi-Aeroelastic hinged wingtip functionality under aerodynamic load and in tip stall recovery.
A year's worth of nuclear grade RPV welding done in just 24 hours with an out-of-chamber EB Welding technique at Sheffield Forgemasters on an SMR reactor mockup.
Guys, this beyond massive.
Gas turbines.
In aerospace, Rolls-Royce is the 2nd biggest global player for widebody aircraft, while CFM, a Safran-GE joint venture, takes 70% of the narrowbody market.
In power generation, Germany's Siemens is another giant, fighting against… yes, GE again.
Big science projects.
CERN, the Large Hadron Collider, the Extremely Large Telescope, the European Synchrotron Radiation Facility, the Joint European Torus, ITER… projects & organizations like these won't grace a stock market Index, but they pay dividends for all humanity.
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…
Mach diamonds.
When a supersonic nozzle is over-expanded (lower pressure than ambient) or under-expanded (higher), a pressure oscillation occurs with compression waves that can coalesce into powerful normal shocks, igniting unburnt fuel.
And so we see diamonds...
As Ireland links more wind turbines and shuts down thermal powerplants, it needs to synchronise all that variable power and add back inertia to the grid lost from decommissioned plants.
So: The world's largest flywheel, 130 tons, & synchronous condensor installed in Moneypoint.
Formula 1
This is a little like saying the US is best at baseball, or Japan at sumo, but the engineering sophistication of F1 teams is no joke, with a tight cluster in the south of England. This white hot crucible of technological competition then feeds other industries…
What's the difference between these two aircraft?
Well a number of things, but one of the biggest is that the A330 on the left is mostly Aluminium, whereas the A350 on the right is mostly composite. This matters.
Find out why & how this happens...
Chocolate.
We'll start with something light.
From mass-market to boutique, Europe is in a class of it's own here. Five countries; Germany, Belgium, Italy, Poland and the Netherlands, make up half of all global chocolate exports. And it's lovely.
Do I really need to go on?
Agriculture.
Specifically, Dutch agriculture: That a tiny country, a fifth of which is reclaimed from the sea, can be the world's third largest agricultural exporter, at over 100 billion Euro a year… is extremely impressive.
This is a ram air inlet, which most airliners have. It stops you from being boiled alive.
You fly in a cabin of clean stratospheric air, replaced every 5 minutes. Pressurising it raises the temperature from - 57C to 95C.
The ram air heat exchanger means this won't kill you.
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!
@eyeslasho
It was stunning.
And just as stunning was 4 years later when the London opening ceremony blew it out of the water by doing something completely different.
Alchemy never died, it super-sized.
Oil refining changed the world, and the world changed refining. It won world wars, saved the whales and gave us wonders.
This thread is a tribute to the Alchemists of Oil!
Minimising wave drag on a supercruiser: It's not obvious at first glance, but the distribution of frontal cross-sectional area on the YF-23 changed very smoothly, minimising wave drag & strong shock wave formation.
Ideal for a fighter designed for supersonic cruising.
1/To find out what's important in aerospace gas turbine design it's best to see what the pros are working on. This is a thread on the Rolls-Royce Ultrafan development engine, and the features that make it special.
Basically, a window into the industry's future.
Extreme Ultraviolet Lithography.
The law of the Internet obliges me to mention ASML, a Dutch company with a near monopoly on the most sophisticated high end silicon chip manufacturing equipment.
Every tech giant depends on their genius.
Production technology.
Germany, Northern Italy & Switzerland are global leaders in the export of machining systems, machining tools, automation technology, machine vision & industrial photonics, placing them in the interesting position of living by tooling-up the competition.
…Supercars.
From pedigrees like Ferrari & Lamborghini through racecar tech inspired McClaren to the swivel eyed insanity of Koenigsegg, the old continent dominates this rarefied industry. The advent of the electric vehicle revolution could yet upend this.
Bypass ratio.
It's easier to accelerate a large volume of air gently than a small volume of air fast…
The bypass ratio is the ratio between the air mass flow through the fan and the flow through the engine core. This number has been going up & up…
Hydrogen: The great white hope of zero carbon aviation.
Cryogenic H2 has three times the specific energy (MJ/kg) as kerosene, but also one quarter the energy density (MJ/L), and needs cylindrical or elliptical fuel tanks.
Designing around this is... not convenient.
Sometimes simple solutions work.
Look closely at the front of many aero gas turbines and you'll see that the very tip of the cone spinner is a different material from the rest. This is a simple, elegant solution to a complex problem.
Icing.
As a little treat for us all, here's an appreciation thread for my favourite NASA X Planes.
From rocket powered spaceplanes through lifting bodies, darts, tailless aircraft, the world's fastest to the eerily quiet, here we go...
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.
Gene sequencing.
The Genomics UK Consortium (COGS-UK) drove much of the world's gene sequencing effort on Covid-19 to understand mutation pathways of the virus and track new variants: By early 2021 it had sequenced almost as many genomes as the rest of the world combined.
Superyachts.
Speaking of unassailable luxury, if you want to show off your ludicrous wealth in style there's no better, more ridiculous way.
With names like Lürssen, Feadship & Oceanco, European manufacturers dominate this bizarre, sophisticated corner of bespoke engineering.
In 2006, the National Institute for Nanotechnology ' the University of Alberta set an unbeatable record: A tungsten Nano-needle tapering to a tip thickness of just one atom.
The sharpest object in the world.
Regulation.
You didn't think I'd leave this out, did you?
We've a planet-worth of bureaucrats in Belgium & Luxembourg. They're over-eager, easy to mock and don't add to our competitiveness, but Food Safety & REACH industrial chemicals regulation are probably Very Good Things.
Ready for a really *niche* technical thread?
Let's talk about cyclonic separators (and how to make them better)!
Full disclosure: I'm an ex-Dyson engineer. There will be bias, and there will be detail.
Possibly, but we're our own worst enemies: We've talent, and create a similar number of startups to America, but our capital markets are shallow, bankruptcy laws muddled and the digital single market isn't one.
As usual, Europe needs to get out of its own way.
Here's hoping.
Medical devices.
Pacemakers, stents, artificial knees, vascular mapping, penile implants… with almost a million people directly employed in medical technology, the continent has you covered.
But the biggest *customer*, by far, is the other big manufacturer, the US.
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…
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!
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?
Covid vaccines.
Like ‘em or loathe ‘em, Europe's status as a pharmaceuticals giant similar to the US meant that most Covid vaccines worldwide had a European company developing them, manufacturing them, or both.
Chip design.
Tiny Arm is a minnow by silicon Valley standards, yet almost every tech firm makes use of it and its chip designs are in most smartphones. A specialist chip designer, this UK firm's small size belies its huge global strategic importance.
An obsidian blade can be encouraged to chip along the lines of it's own molecular lattice, creating a molecular sharpness down to 3 nanometres thickness that no steel can match. It's delicate, prone to chipping and blunting, but obsidian scalpels exist.
Aviation leasing
About a quarter of all the world's commercial aircraft are owned by companies based in Ireland. The globally important but little known aviation leasing industry is so concentrated in the Emerald Isle that it actually makes the country's GDP hard to calculate.
Lightweight materials.
Aluminium is light, but Titanium has a higher strength:weight ratio, and composite fibre reinforced plastics (CFRP) higher still. The proportion of aircraft weight given to super lightweight materials has only grown.
Safe by shape.
Even in the worst case meltdown at Fukushima, the 140+ tons of molten nuclear core never escaped the primary containment vessel (PCV).
This was by design.
The back-office to the world…
If America is designing the new world, and China is building it, it's possible that Europe is the back-office. It specialises in the kind of unglamorous utilitarian niches that the consumer never sees.
Can it be more than that?
Introducing the Tungsten Nano-needle: The sharpest thing on the planet. Produced by electrolytic etching, it can get down to tip thickness below a few nanometres (nm): You can fit 1 million nm into a mm, and 25 million nanometres into an inch.
But we can get sharper...
High on a mountain in the Atacama desert, Chile, the European Southern Observatory is building something immense.
It's called the Extremely Large Telescope, and here's a highlight reel of this beast's ultimate capabilities.
This is a wingtip sail, otherwise known as a winglet or sharklet. You will have seen it on the wing tips of many large passenger aircraft and you may have some kind of idea that it's to do with fuel efficiency.
But how does it work?
@clairebubblepop
"But to expect your kids to be more important than"..
Of course they're more important to me! They're my children. What a daft thing to say. I'll give them every advantage I can reasonably give them in life, because that's part of being a parent.
The first destination will probably be engines for 6th generation fighters, but next gen airliners will follow in time, and with that all of us will, eventually, benefit too.
Let's hear it for yet more unseen innovations!
SWIFT
The hidden plumbing of the world.
A catchy name, the Society for Worldwide Interbank Financial Telecommunications (SWIFT), it's headquartered in Belgium and provides the common messaging that underpins most international payments.
In 2022, SWIFT embargoed Russia.
@Appyg99
Anyone who says either "the US is superior" Or "Europe is superior" is just engagement baiting. There are a hundred reasons you might prefer the US to France or vice versa, all legit.
As for social mobility though, you are statistically wrong, along with many Europeans:
Pumped Hydro .
The most popular solution globally with 150GW power & 9000 GWh energy capacity, this pumps water to an elevated reservoir when electricity is cheap and sends it back through turbines later. After frictional losses, it has a 76%-85% round trip efficiency.
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?