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I thought we already knew that current tokamak designs were very poor in containing plasma due to unpredictable turbulence — ever since the 90s (I remember writ
by moogly 11y ago
I thought we already knew that current tokamak designs were very poor in containing plasma due to unpredictable turbulence — ever since the 90s (I remember writing that in a senior high school-equivalent report on fusion), even. Hence the reignited interest in stellarators.
- drjesusphd 11y agoContaining the plasma isn't really the problem, it's containing the heat. Because of the way turbulence works, you can pump as much energy into the plasma as you want, and all you'll get is more energy leaving the system instead of heating it up.
- stephengillie 11y agoThis sounds like telling Edison and that you can't draw Tungsten wires thinly enough to make the lightbulb work, and he should just go back to gas lamps. The whole article was about learning to predict the turbulence. Now that we have some understanding of the turbulence in a tokamak, should we just continue with stellerators anyway?
- Animats 11y agoEdison didn't figure out how to draw tungsten. Edison figured out a way to make a cheap lamp without tungsten. Frederick de Moleyns, who invented the electric light bulb in 1841, had the right idea - use a metal wire with a really high melting point. He used platinum. Worked, but cost far too much. Edison and Swan figured out how to make a cheap electric light bulb, using carbonized paper. There was a long detour through various forms of carbonized cellulose, including paper, bamboo, and extruded cellulose. Bulb life was short and efficiency was low, but it worked. Then there was a brief detour into tantalum wire around 1902. Finally, Coolidge's process for making ductile tungsten wire was developed at General Electric, and thin tungsten wire could not only be made, but worked easily. Filaments could be coiled up into compact forms. Ductile tungsten lamps came out in 1908. That was it. Incandescent lamps didn't change much over the next century. [1] https://archive.org/stream/menandvoltsstory00hammrich/menandvoltsstory00hammrich_djvu.txt https://archive.org/stream/menandvoltsstory00hammrich/menand...
- harywilke 11y agointeresting stuff. I'd also add that light bulbs got deliberately worse for a while. https://en.wikipedia.org/wiki/Phoebus_cartel https://en.wikipedia.org/wiki/Phoebus_cartel
- TazeTSchnitzel 11y agoDid they recover subsequently, though?
- lutusp 11y ago> I thought we already knew that current tokamak designs were very poor in containing plasma due to unpredictable turbulence ... Yes, and this result suggests that we now have a model that's better at making such a prediction -- more finely tuned to agree with nature.