PPolySim OS
For Hobbyists & Makers · Neutron Transport

Neutron Transport for a coolant loop

Built for hobbyists & makers exploring it for fun. Play with real physics and math, no license and no setup — just open and tinker. Simulate a coolant loop live below — adjust the inputs and watch it respond, right in your browser.

Neutron TransportLive

Controls

Presets

Neutrons do not travel straight — they random-walk through matter, scattering every mean free path and losing energy at each collision. This moderation slows fast neutrons to thermal speeds where they fission efficiently. A short mean free path (dense material) keeps them inside; a long one lets them leak out, which is why reactor size and geometry set criticality.

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Data Inspector

Mean free path30 px
Escaped0 / 40
Leakage0%

Governing equation

Reading this result: A moderate mean free path balances moderation against leakage — enough scattering to thermalize neutrons, but geometry still governs whether the core goes critical.

Runs locally in your browser — free forever. Scale to the cloud when reality gets heavy.

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Frequently asked questions

Is this good for hobbyists & makers?
Yes — this version of "Neutron Transport for a coolant loop" is framed for hobbyists & makers exploring it for fun. Play with real physics and math, no license and no setup — just open and tinker.
Do I need to install anything?
No. It runs in any modern browser, free, with no account required.