engineering

Nuclear Engineering & Reactor Physics

From neutron chain reactions to shielding design — the physics and engineering of nuclear fission reactors, covering criticality, fuel depletion, diffusion theory, decay heat, and radiation attenuation.

nuclear engineeringreactor physicsneutron diffusioncriticalityfuel burnupradiation shielding

Nuclear engineering harnesses the energy released when heavy atomic nuclei split apart. A single kilogram of uranium-235 contains as much energy as 2,700 tonnes of coal — but controlling that energy requires mastering neutron physics, materials science, thermal hydraulics, and radiation protection simultaneously. The margin between a safe reactor and a dangerous one is measured in fractions of a percent of reactivity.

These simulations model the fundamental physics that govern every nuclear reactor. Track the neutron multiplication factor that determines criticality. Watch fuel isotopes evolve over years of irradiation. Solve the diffusion equation to see how neutron flux distributes through a reactor core. Calculate the decay heat that persists for years after shutdown. Design shielding that attenuates gamma rays and neutrons to safe levels.

5 interactive simulations

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Post-Shutdown Decay Heat Curve

Calculate and visualize decay heat production after reactor shutdown using the ANS standard model for fission product decay

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Fuel Burnup & Isotope Evolution

Track the depletion of U-235 and buildup of Pu-239, fission products, and xenon-135 over a multi-year fuel cycle

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One-Group Neutron Diffusion & Flux Profile

Solve the one-group neutron diffusion equation to visualize the spatial flux profile in a bare homogeneous slab reactor

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Reactor Criticality & Neutron Multiplication

Simulate the effective multiplication factor k-eff and neutron population dynamics in a thermal reactor to explore sub-critical, critical, and super-critical states

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Gamma & Neutron Shielding Attenuation

Calculate gamma-ray and neutron attenuation through multi-layer shielding materials with buildup factor corrections