Mediaspace scheduled maintenance: Aug 25, 2026 07:00 - 12:00 AM. During this time, videos will be temporarily unavailable. Check status updates.

Lecture

The Diffusion of Neutrons

In course

PHYS-443: Physics of nuclear reactors

In this course, one acquires an understanding of the basic neutronics interactions occurring in a nuclear fission reactor as well as the conditions for establishing and controlling a nuclear chain reaction. ...

Description

This lecture covers the transport of neutrons, scalar neutron flux, neutron currents, neutron balance, Boltzmann equation, Fick's law, and neutron density. It also discusses fuel cycles, reactor design considerations, and types of nuclear reactors.

Instructors (3)

Andreas Pautz

Mathieu Hursin

Carlo Fiorina

Official source

Ontological neighbourhood

Energy engineering

Nuclear power: Topics in nuclear power

Related concepts (32)

Nuclear reactor

A nuclear reactor is a device used to initiate and control a fission nuclear chain reaction or nuclear fusion reactions. Nuclear reactors are used at nuclear power plants for electricity generation and in nuclear marine propulsion. Heat from nuclear fission is passed to a working fluid (water or gas), which in turn runs through steam turbines. These either drive a ship's propellers or turn electrical generators' shafts. Nuclear generated steam in principle can be used for industrial process heat or for district heating.

Generation IV reactor

Generation IV reactors (Gen IV) are nuclear reactor design technologies that are envisioned as successors of generation III reactors. The Generation IV International Forum (GIF) - an international organization that coordinates the development of generation IV reactors - specifically selected six reactor technologies as candidates for generation IV reactors. The designs target improved safety, sustainability, efficiency, and cost.

Neutron flux

The neutron flux, φ, is a scalar quantity used in nuclear physics and nuclear reactor physics. It is the total distance travelled by all free neutrons per unit time and volume. Equivalently, it can be defined as the number of neutrons travelling through a small sphere of radius in a time interval, divided by (the cross section of the sphere) and by the time interval. The usual unit is cm−2s−1 (neutrons per centimeter squared per second).

Breeder reactor

A breeder reactor is a nuclear reactor that generates more fissile material than it consumes. These reactors can be fuelled with more commonly available isotopes of uranium and thorium, such as uranium-238 or thorium-232, as opposed to the rare uranium-235 which is used in conventional reactors. These materials are called fertile materials since they can be bred into fuel by these breeder reactors. Breeder reactors achieve this because their neutron economy is high enough to create more fissile fuel than they use.

Small modular reactor

Small modular reactors (SMRs) are a proposed class of nuclear fission reactors, smaller than conventional nuclear reactors, which can be built in one location (such as a factory), then shipped, commissioned, and operated at a separate site. The term SMR refers to the size, capacity and modular construction only, not to the reactor type and the nuclear process which is applied. Designs range from scaled down versions of existing designs to generation IV designs.

Related lectures (32)

Neutron chain-reacting systems

Explores chain reactions, multiplication factor, fuel cycles, reactor design, and types of nuclear reactors, ending with a summary of key concepts.

Physics of Nuclear Reactors: Fundamentals and Advanced Concepts

Explores the fundamentals and challenges of nuclear reactors, covering neutron diffusion, fission, breeding, transmutation, and advanced technologies.

Reactor Technology: Reactivity Variations and Control

Explores reactivity variations in reactor technology, covering short-term, medium-term, and long-term effects, means of control, and consequences.

Nuclear Reactors: Concepts and Analysis

Explores nuclear reactor physics, covering basic principles, specific reactor types, accidents like Chernobyl, and advanced technologies.