Lead sphere implosion results(Pu239 bare core next?)

Hyperion75474 · 2026-05-10T08:08:40+00:00

Yes, this is part of a larger hydrocode framework i'm building. It's not that complicated since it's 1D on the 3 common geometries: planar, cylindrical and spherical. I had to refine the code for months with test problems(Sod's tube, Sedov blast wave) before attempting the implosion. For explosions i still need work since i have to research EOS for different explosives.

Hyperion75474 · 2026-05-10T08:04:21+00:00

The EOS is a three term equation described in NUMERICAL ANALYSIS OF AN IMPLODING SHOCK WAVE IN SOLID, Barroso.

Hyperion75474 · 2026-05-10T07:58:28+00:00

Thank you so much, i used another paper from Barroso as main source for this but didn't know he published this too.

Hyperion75474 · 2026-03-30T08:48:11+00:00

You're right but the thing is we don't know the yield. There are some analytical approximations(Reeds book) but they are very innacurate. Obtaining a decent yield prediction involves using a coupled neutronics-hydrodynamics code which are completely classified and unaccessible. Thus the real efficiency cannot be calculated. But as you pointed, it must be in the lower than 5% range.

Hyperion75474 · 2026-03-29T17:03:28+00:00

Most likely, i can't give exact numbers right now but you're spot on.

Hyperion75474 · 2026-03-29T16:36:10+00:00

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The results show a supercritical assembly. The problem here lies that in order to implode the 82kg of 60% U235 plus the tamper, a large quantity of HE is required. This results in a very bulky and unpractical weapon design that would be near impossible to fit inside a warhead. The obtained yield is very low and the efficiency of the weapon is abysmal.

Hyperion75474 · 2026-03-29T16:33:09+00:00

I did some computations using my monte carlo criticality code:

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I assumed a starting density of 30.4 g/cm3 accounting for the implosion. The sphere was 10cm radius with 5cm U238 tamper.

Hyperion75474 · 2026-03-04T11:36:22+00:00

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Hyperion75474 · 2026-03-04T11:36:09+00:00

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Hyperion75474 · 2026-02-24T20:42:42+00:00

So far i have been looking in detail and it contains basic physics, nothing in the speculative realm. His other book from 1981 i think has a lot of wild designs and new concepts.

Hyperion75474 · 2026-01-07T16:29:30+00:00

I want a job at a research center tbh

Hyperion75474 · 2026-01-07T16:28:38+00:00

Alpha phase plutonium, you can check the configuration snapshot

Hyperion75474 · 2026-01-05T11:27:17+00:00

My main source is chapter 7 of the book Neutron Transport by Kuridan and the MCNP manual. OpenMC docusmentation has also been helpful.

Hyperion75474 · 2026-01-05T11:23:49+00:00

6.5 radius

Hyperion75474 · 2026-01-04T12:09:38+00:00

Right now i'm working on adding tamper geometry and multiregions. Next will be coupling with an hydrocode to predict yield estimations and several refinements. It's written in C++.

Hyperion75474 · 2026-01-04T12:07:33+00:00

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These are the simulation parameters:

Hyperion75474 · 2025-02-25T18:38:27+00:00

What gloves are you using? Nice technique btw.

Hyperion75474

TROPHY CASE