How do gas core nuclear reactors work?

[Urvabara]

"The Cavradyne engines were based on the assumption of years of research and development, during the 1980s and '90s, of gaseous core nuclear reactors and high-temperature ionized gases. Theory was presumed to have shown that gaseous uranium-235 could be made critical in a cavity reactor only several feet or meters in diameter if the uranium atomic density were kept high, and if temperatures were maintained at a minimum of 20,000 °F (11,400 K). At first, progress was slow because of such early unsolved problems as how to reduce vortex turbulence in order to achieve high Separation ratios, and how to achieve adequate wall cooling in the face of the thermal radiation from the high-temperature ionized plasma. In the Cavradyne system, the temperature of the reactor was not directly limited by the capabilities of solid materials, since the central cavity was surrounded by a thick graphite wall that moderates the neutrons, reflecting most of them back into the cavity. Wall cooling would be ensured by circulating the hydrogen propellant prior to its being heated. Fissionable fuel energy was said to be transferred to the propellant by radiation through a specially designed rigid -- and coolable -- container."

So, what do you think of the above text? Are there any scientific inaccuracies?

Where can I find more information about cavity reactors?

"...gaseous uranium-235 could be made critical in a cavity reactor only several feet or meters in diameter if the uranium atomic density were kept high, and if temperatures were maintained at a minimum of 20,000 °F (11,400 K)" <-- Any references to this statement? Anyone?

Thank you!

Henri.

 

[anorlunda]

ping @Asymptotic

 

[Asymptotic]

ping @Asymptotic

Wish I could help, but the closest I've come to nuclear is working with Betamike gauges using Strontium-90 sources.

 

[Rive]

Google says the original text is from movie 2001: A Space Odyssey (or from some books behind it).
According to the wiki page about 'gas core reactor rocket' the problems mentioned in the text are actually correct. Considering the nature of Sci-Fi the solutions for the mentioned problems likely should be taken as sophisticated high grade technobabble, not really worth any debunking or confirmation.
The thread is from 2008: already eleven years old.