21–30 of 125 posts
What would the effects be of releasing nuclear waste in space? Could we sent up all of our nuclear waste, put a rocket on it and just let it disappear into the distance?
How about just sending it to the moon instead? Perhaps then we could use the moon as a giant space ship by blowing up the nuclear waste?
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Stirling engines are not efficient. Using that heat to make steam to turn a turbine is much more efficient. But it would be harder to make that portable.
Yes they are. An ideal stirling engine has the Carnot level efficiency, i.e. maximum theoretical efficiency for a heat engine. https://blog.mide.com/thermodynamic-theory-of-the-ideal-stir...
Earlier quoted context omitted.
Yes they are. An ideal stirling engine has the Carnot level efficiency, i.e. maximum theoretical efficiency for a heat engine. https://blog.mide.com/thermodynamic-theory-of-the-ideal-stir...
Except the ideal one doesn't exist and multistage stream turbines are more efficient in practice.
For those curious, this uses a nuclear reactor to power a Stirling engine.Stirling engines are a good choice because there is no mass transfer to create the work (i.e. no fuel needed, just heat). It only needs a temperature differential and sealed gas/liquid to work. I highly recommend to read more about Stirling engines since they are of one the most efficient form of work generation with just a temperature differen…
Stirling engines are not efficient. Using that heat to make steam to turn a turbine is much more efficient. But it would be harder to make that portable.
They invented and are very close to commercializing a direct heat-to-electricity converter that uses acoustic waves. No moving parts. Close to 30% efficiency.
Earlier quoted context omitted.
Wouldn't "passive decay" mean it's not based on fission -- but the article and video both mention fission...?
Passive decay is still fission, it's just not artificially sped up fission :) it's probably more complex than that. Is high speed natural decay of an artificially created or enriched heavy element natural or artificial? I'm not sure how that gets classified.
[0] https://en.wikipedia.org/wiki/Natural_nuclear_fission_reacto... - your terminology immediately made me think of this
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It's a fascinating idea from science fiction perspective, but moving the Moon anywhere will probably have devastating effects on the Earth's biosphere
I think that's just short term thinking: When the sun expands into a red giant, the gas drag will slow down the moon. I think that means it will crash into the earth if it's not removed before.
For those curious, this uses a nuclear reactor to power a Stirling engine.Stirling engines are a good choice because there is no mass transfer to create the work (i.e. no fuel needed, just heat). It only needs a temperature differential and sealed gas/liquid to work. I highly recommend to read more about Stirling engines since they are of one the most efficient form of work generation with just a temperature differen…
Stirling engines are not efficient. Using that heat to make steam to turn a turbine is much more efficient. But it would be harder to make that portable.
Conspicuously not mentioned: what kind of design the reactor uses. Thanks engadget, 10/10 reporting. Based on the wikipedia article, it looks like a passive decay heater attached to a bunch of sterling engines. Pretty much a souped up RTG that trades more energy output for having moving parts. Neat.
[...] the core of the reactor will be of solid, cast uranium-235 surrounded by a beryllium oxide reflector. This reflector focuses neutron emissions and returns their energy back into the core to minimize nuclear gamma radiation [...].
Nuclear reaction control is provided by a single rod of boron carbide which is a neutron moderator that is initially fully inserted, [...]. Once the moderator is extracted the nuclear chain reaction will start but can not be stopped completely, although the depth of insertion provides a mechanism to adjust the heat output [...].
Passive heat pipes filled with liquid sodium then transfer the reactor core heat to one or more Stirling engines, which converts heat into rotary motion that drives a conventional electric generator.
What would the effects be of releasing nuclear waste in space? Could we sent up all of our nuclear waste, put a rocket on it and just let it disappear into the distance?