On 11 Mar 2019 at 1:15, Richard Aiken wrote:
> http://www.projectrho.com/public_html/rocket/enginelist.php#id--Nuclea
> r_Thermal--Gas_Core--Open_Cycle--Nuclear_Salt_Water
>
> I am thinking that this would be just the thing for a
> Flash-Gordon-style "atomic rocket ship." Unfortunately, I don't have
> enough math to understand the calculations, so I was hoping someone on
> the list could let me know how to model one of these, in terms of the
> simple Book 1 Classic Traveller shipbuilding rules.
The exhaust will make environmentalists cringe.
Well, yeah. But in a Flash-Gordon-style world, "environmentalist" is a term which hasn't yet been coined. Plus - from what I've been reading - the increase in long-term radiation wouldn't amount to much above background. Especially if this continuous "squib" explosion occurs mostly in the air or open sea. Nothing there to create fallout, after all.
> By the way, since the rocket's fuel is stored in discrete
> small-diameter tubes to prevent inadvertent critical mass, battle
> damage would result in [according to the website author] "a nuclear
> explosion inside the ship." But since the fuel only explodes upon
> reaching critical mass, if one were to thread the tubes throughout the
> outer layer of hull and equip each line segment it's own explosive
> reactive armor [to expell and scatter the fuel from the damaged line
> before it could react], you should be able to prevent uncontrolled
> reaction.
Critical mass depends on shape. *Strongly*. Some day I gotta find the
issue of Analog from the early 60s that has a fact aarticle about it
and scan it. I've got it, it's just buried in storage.
I'm fairly sure the designer allowed for this. The associated drawings depict a reaction chamber with multiple water supply jets.
In a liquid, density has effects as well. I'd be really worried about
compression waves in that "salt water" setting off a chain reaction.
Well, you sort of want a chain reaction, don't you? You just want it to happen in the rocket nozzle, rather than the fuel lines. If said fuel lines are small and segmented, you'd have to have a case of *really* bad timing to allow a runaway reaction. Of course, the article does have a little sidebar about (in the fictional game world where these rockets appear) engineers calling the injectors that regulate the fuel feed "wileys" . . . possibly named after a certain cartoon coyote. :)
Just venting the fluid should do. It'll scatter rapidly. Also, as the
water evaporates, that makes it *harder* for a reaction to occur (the
water acts as a moderator, slowing neutrons which increases the
reaction rate.
The article mentions that the designer supposes that pumping a shell of water around the reaction ought to be enough to control stray neutrons.
Leaks inside are a problem because they can form "puddles" whose
shape and volume would cause chain reactions.
Check.
Mind you, without some sort of confinement, you won't get a "boom".
at most a "squib" explosion that would scatter the fuel. More like a
quick boil and a radiation flash that could be really bad for
equipment and personnel.
So a short-lived rocket blast. Therefore, maybe mount these rockets on pylons that incorporate their fuel lines, so that any wayward blasts don't involve the rest of the ship?
BTW, I'm still hoping for some helps with Classic Book 1 style construction! :)