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China Just Made a Major Breakthrough In Nuclear Fusion Research (techienews.co.uk)
New submitter TechnoidNash writes: China announced last week a major breakthrough in the realm of nuclear fusion research. The Chinese Experimental Advanced Superconducting Tokamak (EAST), was able to heat hydrogen gas to a temperature of near 50 million degrees Celsius for an unprecedented 102 seconds. While this is nowhere near the hottest temperature that has ever been achieved in nuclear fusion research (that distinction belongs to the Large Hadron Collider which reached 4 trillion degrees Celsius), it is the longest amount of time one has been maintained.
It is the second Tokamak reactor that China has built and it has been around for about 10 years. There is no inherent reason to disbelieve them. They have come a long way from 20 years ago.
From what I have read China are claiming a significantly lower temperature than the recent German test, approx 30 million degrees K lower, but a much longer duration. The Germans also believe that their system will comfortably run for much longer, the recent operation was just a test so potentially we are seeing a point where engineering capabilities can produce the accuracy of design needed for tokamaks to work.
An interesting trend to watch, even if this one doesn't turn out to be verified, is that China is where most of the the significant energy research is happening.
The US will be buying most of its advanced energy tech from China in just a couple decades. A couple decades ago that would have seemed unconscionable.
Say what you want about the relative historical value of the two governments, but one stymies progress with fear-based regulations and denial and the other takes the engineering approach to solving problems. Only one of those can drive prosperity - the leads to despair.
My God, it's Full of Source!
OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
It takes billions (not millions) of years for hydrogen atoms to fuse in the sun - that is precisely why the sun has a billions-of-years lifetime. So in building a fusion reactor, we need many orders of magnitude higher reaction rates, and to achieve them at many orders of magnitude lower densities. One way of doing this is to have much higher temperatures. The solar core temperature is about 15 million degrees and TFA has 50 million degrees for this new result, and 80 million degrees for half a second at a European reactor. This sounds unimpressive, but the reaction rates are very sensitive to temperature - proportional to about T^8 as I recall, but I didn't quickly find an online reference for this. 75 million degrees would therefore give a boost of about 5^8 which is about 400,000.
In the sun, the first reaction in the chain (proton+proton->deuterium) is the rate limiting step. In a reactor, we can provide deuterium enriched fuel and bypass this step. I don't know what the reaction rates are, but I suspect that this will be a greater benefit that the higher temperatures. You can do even better with tritium in the fuel, but your reactor becomes an intense neutron source, leading to induced radioactivity in nearby materials. Some proposed designs use these neutrons to breed more tritium from a lithium blanket around the reactor. (Once I get beyond the proton-proton chain reaction, I'm just relying on pop-science knowledge, so corrections from the more knowledgeable are welcome.)
Stars a bit more massive than the sun burn hydrogen via the CNO cycle, which has even higher temperature dependence (from memory, about T^17). I've never heard of anyone suggesting using the CNO cycle in a fusion reactor - presumably there are good reasons, but I don't know what they are. One problem is you need to wait for radioactive decays, but these have half-lives on the order of 1 to 2 minutes, and a commercial reactor would be running for much longer than that.
Quattuor res in hoc mundo sanctae sunt: libri, liberi, libertas et liberalitas.
https://www.lenr-forum.com/forum/index.php/Attachment/386-IEEE-brief-DeChiaro-9-2015-pdf
Dear reader, I quit reading this document as soon as I saw convicted fraudster and scam artist Andrea Rossi cited by it unironically -- as you should as well.
Hot fusion is also going nowhere until anuetronic fusion becomes practical (pro tip: it's quite a bit harder to do) because the fast neutrons eventually destroy every known material used as the plasma-facing "first" wall. That's something the ITER fanboys are not telling you (for obvious reasons).
"Politicians and diapers must be changed often, and for the same reason."
The LHC experiments concern high-energy particle physics, not fusion research. It is operating at energy scales well above plasma [unless you want to talk about "quark-gluon plasma, which is something else entirely] and at conditions which have nothing to do with nuclear fusion.
A practical fusion reactor has temperatures higher than the sun, because the sun has a horrible power density. Fusion reactions in the sun generate only about 100 wattas per cubic meter, and you need a lot more than that to get a net gain in a human built reactor of a reasonable size. The target is usually around 10 keV for DT fusion, or about 120 million K.
Keep in mind this is China's news, the same ones who tell us Taiwan/Hong Kong/Tibet/South sea islands is belonged to China, nothing bad ever happen on Tiananmen square, there is no corruption in China (except a few to make example of, the rest of the world is polluted as bad as China (lol no) and countless other lies about their country to surpress to people/save face.
Here is why it's not the USA - scroll down to the graph for the very quick answer:
http://hardware.slashdot.org/s...
China is also dumping US 1960's-style money in to scientific research and development. Of the three major space-faring countries, China, Russia, and the USA, you'll note that only China and Russian currently have manned spaceflight programs.
China has also built the largest ground recieving dish in the world, out-doing the one in Puerto Rico by a factor of almost two.
China is rocking the 1960s American Science Research meme so hard it hurts.
Meanwhile, American politicians are arguing about whether or not climate change is real, and we slot somewhere between countries like Latvia and Lithuania in Science globally. Hong Kong, (china), Singapore, and Japan are #1,2,3 globally, if you were curious.
moox. for a new generation.
Um... the US spends more money on R&D than any other country, and more money per person than any other country except Israel and South Korea.
https://en.wikipedia.org/wiki/...
There are a lot of posts about how we can't trust China, but for any one who has followed fusion work, this should be no surprise. EAST has been one of the major research tokamaks in the world, and results like this are incremental results that were expected to come about. What is more interesting is how cheap EAST and some other Chinese fusion research facilities are, like KTX which I am more familiar with and has been both cheap and fast. Yet they still contribute new results and share info at conferences, so it is not like they are just a lagging copy of other countries.
You seem to not be aware that fusion research is an open and collaborative project between all nations. We share data, equipment, tokamak run-time, and scientists. Your partisan suspicion is understandable for someone not in the know, but it's totally wrong. The fusion scientific community is well aware of what is going on at EAST (and all other major collaborative facilities), when the machine turns on, when it turns off, when there is a leak, when a diagnostic malfunctions, and when things go well.
At DIII-D (USA), we have built a "remote control room" for EAST and KSTAR so that researchers in US can operate EAST on the third shift when our colleagues in China are sleeping. Control parameters will be transferred to Hefei over the internet and diagnostics will be fed back to the monitors in almost real time.
BTW, I am a fusion research scientist based in US, but I do do some work on EAST as well as other machines.