4 ms·

Yes they're right about it. Your first link says that water-cooled reactors can produce steam up to about 300 °C, which is accurate. The hottest outlet tempera

Yes they're right about it. Your first link says that water-cooled reactors can produce steam up to about 300 °C, which is accurate. The hottest outlet temperature today from a nuclear reactor is about 1000 °C from HTTR in Japan, but that's fairly exotic. There have been hotter outlets back in the NERVA nuclear rocket days. Also exotic. Good read is this one: https://www.iaea.org/publications/8692/advances-in-nuclear-power-process-heat-applications https://www.iaea.org/publications/8692/advances-in-nuclear-p...

perihelions 5y ago
- "There have been hotter outlets back in the NERVA nuclear rocket days. Also exotic." Though, those were rocket engines with a design lifespan of several minutes. It's not possible to sustain temperatures like that, is it? (I am not an engineer). I remember reading that one of the NTR test firings saw bits of molten corium flying out in the exhaust plume.
- rich_sasha 5y ago
  Jet engines get way hotter for sustained periods of time: https://aviation.stackexchange.com/questions/74362/how-hot-do-internal-parts-of-jet-engine-get https://aviation.stackexchange.com/questions/74362/how-hot-d... (And the crazy thing is, if you think about it, they are also gas turbines! The bough I guess perhaps your question was more specific to the reactor itself)
  - perihelions 5y ago
    Am I misreading your link? I see temperatures listed "only" up to 2,000 K; but the successful NTR tests went up over 2,500 K. (Excluding the failed ones that melted, of course). - "The average exit gas temperature was 2,550 K (2,280 °C), the highest ever recorded by Project Rover. The chamber temperature was 2,750 K (2,480 °C), another record." https://en.wikipedia.org/wiki/Project_Rover https://en.wikipedia.org/wiki/Project_Rover There's also one notable difference: internal combustion turbines see their highest temperatures in the gas phase, which is somewhat insulated from the turbine blades (by weird fluid dynamic effects I don't understand). No solid material needs to withstand the peak temperature. https://en.wikipedia.org/wiki/Turbine_blade#Film_cooling https://en.wikipedia.org/wiki/Turbine_blade#Film_cooling
    - rich_sasha 5y ago
      I was focusing on turbine elements with temperatures well in excess of 1000 deg C, which is much higher than the temperatures described above. Indeed, exhaust gases are even hotter. I believe turbine elements are cooled by grouch internal channels these days, which is quite mind blowing.

perihelions 5y ago

- "There have been hotter outlets back in the NERVA nuclear rocket days. Also exotic." Though, those were rocket engines with a design lifespan of several minutes. It's not possible to sustain temperatures like that, is it? (I am not an engineer). I remember reading that one of the NTR test firings saw bits of molten corium flying out in the exhaust plume.

rich_sasha 5y ago
Jet engines get way hotter for sustained periods of time: https://aviation.stackexchange.com/questions/74362/how-hot-do-internal-parts-of-jet-engine-get https://aviation.stackexchange.com/questions/74362/how-hot-d... (And the crazy thing is, if you think about it, they are also gas turbines! The bough I guess perhaps your question was more specific to the reactor itself)
- perihelions 5y ago
  Am I misreading your link? I see temperatures listed "only" up to 2,000 K; but the successful NTR tests went up over 2,500 K. (Excluding the failed ones that melted, of course). - "The average exit gas temperature was 2,550 K (2,280 °C), the highest ever recorded by Project Rover. The chamber temperature was 2,750 K (2,480 °C), another record." https://en.wikipedia.org/wiki/Project_Rover https://en.wikipedia.org/wiki/Project_Rover There's also one notable difference: internal combustion turbines see their highest temperatures in the gas phase, which is somewhat insulated from the turbine blades (by weird fluid dynamic effects I don't understand). No solid material needs to withstand the peak temperature. https://en.wikipedia.org/wiki/Turbine_blade#Film_cooling https://en.wikipedia.org/wiki/Turbine_blade#Film_cooling
  - rich_sasha 5y ago
    I was focusing on turbine elements with temperatures well in excess of 1000 deg C, which is much higher than the temperatures described above. Indeed, exhaust gases are even hotter. I believe turbine elements are cooled by grouch internal channels these days, which is quite mind blowing.