5 Megawatt Nitinol Engine by Mcdonnell Douglas (2015) [video]
youtube.com
youtube.com
It seems like it has a huge potential in nuclear plants
Amazing, seeing this I feel like I've found bigfoot.
If it can extract useful work from merely warm water, it would seem like the ideal thing to maximise the overall thermal efficiency of a large power plant.
My theory here is that running all the stems, stalks, and roots that you don't use from stuff like annual food crops through a wood chipper or something should macerate the cell walls enough to allow the yeast to feast, at least.
material fatigue. basically the nitinol springs/belts/strips eventually breaks.
so it's a high maintenance low-efficiency (hard to scale) system compared to regular steam turbines.
... though of course the latter is in development for ~250 years, so it has a bit of a head start.
so it seems like very much part of modern materials science. (and I'd guess bimetals are standard in many heat-related engineering applications, nitinol is just special because of how fast it changes shape, and because it's an alloy not 2 pieces of metal stuck together.)
https://en.wikipedia.org/wiki/Nickel_titanium#Biocompatible_...
This device seems more useful for generating mechanical motion at the point of use, rather than generating electrical power. I'm envisioning solar and hydro-powered pumping systems that operate in remote environments, like the third engineer interviewed in the video. He proposed that the engine could be used to pump water solely due to the temperature difference between the pumped fluid and the air.
Another interesting thing would be to run the system in reverse to turn mechanical energy into a hot and cold fluid. I haven't thought it through deeply, but it seems superficially similar to elastic band refrigerators[0,1].
[0] https://www.science.org/doi/10.1126/science.aax6182 [1] https://www.science.org/content/article/fridge-made-rubber-b...
And the efficiency of the Carnot engine is 1-T_cold/T_hot, both temperatures expresssed in Kelvin. Room temperature water is 300K (that's by convention, this translates in 27 C or 80 F). Let's say warm water is at 333K (that's more like scalding hot, at 60 C or 140 F). The Carnot engine efficiency is then going to be 1 - 300/333 = 10%.
So, not engine can exceed 10% efficiency when using scalding hot water, for merely warm water it's probably going to be 5% or less.
[1] https://en.wikipedia.org/wiki/Second_law_of_thermodynamics#C...
None of what he showed me made sense, so i wrote it off. I know hydrogen power is a thing, i just know that you can't generate enough power with hydrogen to crack water into hydrogen at the rate needed to sustain that, so having all that crap in the vehicle - assuming it worked at all - seemed dangerous, at the very minimum.
Now, i'm sure if you had solar panels - at home[ed.] - and a safe way to compress the hydrogen into small tanks somewhere on the vehicle, you could get a few dozen miles probably fairly safely. And i'm not sure if anyone has patented this yet, but resin/epoxy/plasticize/rubberize the exterior of a carbon fiber tank to store the hydrogen eliminates most of the safety issues, i think.
For most of their applications a current was applied to the wire that would heat it up and cause it to spring out straight, then as it cooled the wire would recover. Not particularly fast actuation but quite controllable.
[1] https://musclewires-com.3dcartstores.com/Muscle-Wires%C2%AE-...
i suspect Dynalloy nabbed up the trademark in 2004 after the original owner of muscle wire (1992) failed to keep up the fillings in 2003.
Buy some wire of your own: http://www.tinialloy.com/livewire.html
(I worked there quite a while ago)
Any news on this?
An interesting successful application was the Frangibolt - a non-explosive way of breaking bolts to separate components of an assembly in space.
Nitinol is used in lots of vascular devices. At least in my company, they used it first in guidewires just for the super elasticity, as a torturous vessel may kink a steel wire.
At first there were bare metal stents, steel and later CoCr alloy. But last 15 years or so we've gotten self expanding stents that use the shape memory effect to set the final diameter at body temperature during processing, then the Stent is collapsed down into a catheter delivery system. There are various designs for releasing the collapsed Stent into the vessel, but once there it springs open thanks to super elasticity and apposes (conforms) up to the vessel wall, where good apposition gives lower chance of thrombosis formation.
There are lots of other devices too... embolic protection devices (niti frame with a net over it, to catch shmoo from flowing to brain during a carotid procedure ) And various heart repair devices.
It's great for intervention devices because you can collapse a device down small enough to be advanced by radial or femoral artery access and let's you do things that would normally require cracking someone's chest open for heart surgery.
But the material is finicky, and it could take a decade for a smelter to get their niti process worked out. A very small difference in alloy composition disproportionately affects the crystal structure transition temperature, which impacts whether device will behave in service conditions
Meanwhile, nitinol actually works via a quantum property, and is sucking energy out of a sister universe.
You don't care because cheap and free, but they do! Doubly so because it sucks power at the easiest parallel source, which are (in their universe) simple copper wire.
Worse, the power stolen is 1000x of times that received, meaning they have been having significant power losses on long power runs.
This means that they have to setup more local generating power, as long power transfer from hydro dams, and clean central sources won't work.
More coal, natural gas, thanks to you! And global warming is far more advanced there.
But you don't care, eh?
When will people learn.
Funny story, the setting of part 2 was so different to part 1 that I mistook the book for a collection of novellas until more than half way through.
It'd be interesting to try to propel a ship with the temperature differential between air and water.
Note that no 5 MW engine was demonstrated in this video. It's just a figure that engineer guesstimated as a plausible combined power output of multiple stacked engines. Quote at 3:05.
When the wire is strongly deformed, the phase transition causes it to absorb heat from its surroundings; as a result the area around the small pulley becomes colder.
When this strain is released, the phase transformation is reversed and it will release heat to its environment.
As a result, the cold reservoir gets colder and the hot reservoir gets hotter.
I still wonder why I've never seen even a demonstration prototype of this effect.
/s
This is some great science education!
> Buehler was looking at alloys with two solid states as possible materials for the nose cone. He had selected roughly 60 alloys for further examination from a book entitled Constitution of Binary Alloys–nitinol being one of them. When he made the ingots for testing, he intentionally dropped one of the cold ones on the floor. Hoping to hear a clear bell-like ring, indicating that the metal had the properties he was hoping for. Instead, it returned a dull thud–similar to dropping a sack of flour on the ground. Worried that the ingot was filled with internal flaws, he dropped one of the ingots that hadn’t cooled yet. This returned a wonderful bell-like ring. However, after the ingot had been cooled in water, it returned a dull, leaden thud, just like the first one. This is the first indication that nitinol had a substantially different double state. Buehler named his alloy nitinol for Nickel-Titanium Naval Ordinance Laboratories. All of this occurred in 1959. However, the shape memory aspect of nitinol wasn’t discovered until a lab meeting in 1961. Buehler had been performing tests to determine the fatigue life of nitinol by bending a strip into an accordion like shape over and over again. His project was brought under review and his technician was demonstrating the fatigue properties to senior officials. During this presentation, one of the officials present heated the nitinol with a lighter, at which point it rapidly straightened out. This, of course, sent ripples throughout the scientific community. This material could take low grade heat and generate mechanical energy! Numerous scientists began experimenting with how to build engines with nitinol that would take low grade energy and transform it into very high grade energy that could be used to do work. This culminated in the Nitinol Heat Engine Conference, hosted by the Naval Surface Weapons Center (previously Naval Ordinance Labs) in 1974. At the Nitinol Heat Engine Conference, the NSWC gathered together the top scientists who had been working on nitinol to discuss what had been done and what still needed to be done to make nitinol heat engines a reality. The presentations from this conference are available in the book Proceedings of the Nitinol Heat Engine Conference. At this point, the activity surrounding nitinol seemed to all but dry up and disappear. Prior to the conference, nitinol researchers were featured on news channels like CNN and BBC. Afterwards, there was little to no attention given to nitinol by major television networks for over twenty years. This led to all kinds of conspiracy theories ranging from nitinol being kept for top secret government experiments to nitinol being an alien technology that was discovered in the Roswell accident. However, the reality is very different. Behind the scenes, material scientists were working hard to figure out HOW nitinol worked.
> In order to fully optimize a nitinol heat engine, it must be understood what happens when nitinol undergoes the shape memory effect. This will be discussed in greater detail in chapter 2. The next time nitinol appeared in public, it wasn’t referred to as nitinol, it was called just plain titanium. Of course, this is a misnomer since nitinol is slightly more nickel than titanium. This new public appearance didn’t even exhibit the shape memory effect as people were so excited about earlier. No, this was completely different and it was marketed under the trade name FlexonÒby the company Marchon Eyewear. Released for public sale in 1995, Flexonâwas unusual in that you could bend it through incredible distortions and it would just snap back to its original shape once you released it. Once Nike began to use it in their Vision line of glasses, athletes everywhere began buying it up. Gone were the days of breaking your glasses on a regular basis just because you lived an active lifestyle. You could sit on them, you could intentionally bend them, you could tackle someone in football, and they would just bounce back. These glasses would forgive those bumps and bangs over and over again–seemingly forever. People who broke their glasses every six months now could go several years on a single frame. The frames were termed ‘superelastic’. Once superelastic nitinol was discovered, it wasn’t long before surgeons began using it as they worked on people. Vascular stents was one of the first applications because the stent could be folded so flat that it could be inserted through the tiniest of holes into the patient’s bloodstream–minimizing recovery time. Once in place, the superelastic nitinol wire could withstand severe deformation and outlast stainless steel by an order of magnitude. To put this in perspective, superelastic nitinol stents were capable of undergoing a 30% deformation with a cycles to failure life expectancy greater than 10,000,000. Stainless steel, on the other hand, could withstand a deformation of just 0.5% with fatigue life of around 1 million cycles.
I am pretty sure there are many uses to be discovered yet. I suggest everyone here buy a few samples to play with.
*Drank that chance away :) Ended up graduating 16 years later from FAU - Home of the fighting burrowing owls!!
Hmmm. Is this possible?
From Wikipedia article on Nickel-Titanium:
"A great deal of pressure can be produced by preventing the reversion of deformed martensite to austenite—from 35,000 psi (240 MPa) to, in many cases, more than 100,000 psi (690 MPa). One of the reasons that nitinol works so hard to return to its original shape is that it is not just an ordinary metal alloy, but what is known as an intermetallic compound."
So yeah, there or thereabouts.
I highly doubt the chemists and physicists who built that precision engine would have been able to do it without a fairly decent understanding of what was actually going on at the materials level, at least something better than 'nobody knows!'.
I can't remember the youtuber offhand, but there was another question about the "speed of electrons" in a long wire, with actual experimentation to determine the speed. It gets dangerously close to faster than light communication for my tastes so i don't really remember the thesis and arguments offhand, my brain just gets warm.
"Sanders' CNN reports on Nitinol, a new metal energy conversion system won the US Engineer's Award for Broadcasting Excellence. His follow-up articles in Science Digest were translated in German and republished in Japanese by Japan Times in their annual selection of the world's best science reports. Sanders is working on a follow-up article and an update documentary for world release on new and startling disclosures on the origins and potential of Nitinol. )...
His accent is the "broadcast accent" that was cultivated at the time. If you can lay your hands on a copy of Peter Weir's The Year of Living Dangerously[2] you'll hear a young Mel Gibson switch between his normal and a broadcast accent for his scenes in the recording booth.
[1] https://www.imdb.com/name/nm1467242/
[2] https://www.themoviedb.org/movie/11541-the-year-of-living-da...
No worries, I got your meaning.