Nuclear engineering

Nuclear engineering is the practical application of the principles of nuclear physics and the interaction between radiation and matter. This field of engineering includes the design, analysis, development, testing, operation and maintenance of nuclear fission systems and components, specifically, nuclear reactors, nuclear power plants and/or nuclear weapons. The field can also include the study of nuclear fusion, medical applications of radiation, heat transport, nuclear fuels technology, nuclear proliferation, and the effect of radioactive waste or radioactivity in the environment.

Contents

1 Overview

2 Specialties

2.1 Fission
2.2 Fusion
2.3 Nuclear medicine

3 Nuclear Engineering Organizations

4 See also

5 External links

Overview

Nuclear engineering is the study of engineering the transfer of useful work using knowledge of the atomic nucleus gleaned from nuclear physics which researches the theories about the forces that bind the nucleus. A nuclear engineer is first trained in basic physics followed by quantum mechanics which then leads into atomic physics and nuclear physics. From here, a nuclear engineer takes courses dealing with radiation protection and detection.

Whereas nuclear fusion specialization echoes nuclear physics, nuclear fission and nuclear medicine are very much with us today. The USA gets about 20% of its electricity from nuclear power, and medicine would be medieval without nuclear medicine. From x-ray machines to MRI to PET among many others, nuclear medicine provides most of modern medicines diagnostic capability along with providing many treatment options.

The nucleus is the center of the atom and can consist of neutrons and protons. The strong nuclear force is what keeps the nucleus bound together, while the weak nuclear force is responsible for certain types of radioactive decay. Just like the electrons in the atomic shell model, the nucleus exibits quanta which also result in a nuclear shell model. That is, there are specific energy levels in the nucleus where certain reactions are likely to occur.

Radiation is anything which "radiates" away from the atom. We commonly classify the most common types as alpha, beta and gamma radiation. Alpha radiation consists of alpha particles which are basically just fully ionized helium nuclei. They contain 2 protons and 2 neutrons. Beta radiation consists of beta particles which are either an electron or a positron (the anti-matter equivelent of an electron). Gamma radiation is a very high energy photon.

Neutrons are most important in fission-based nuclear reactions since they are neutral and will not lose their energy except through collisions. The cross-section of the target nucleus is also vitally important.

Radiation existed long before nuclear engineers. We are surrounded by it owing to the fact that the solar system itself is the remnants of a much earlier star. The fusion reactions inside the star created all the elements in the periodic table (in nuclear engineering we use the Chart Of The Nuclides which takes into account all the isotopes) and most of these were radioactive. It is estimated that life took as long as it took to appear because the Earth had to 'cool off' radioactively. Also, our part of the galaxy is far enough away from the turbulent galactic center to avoid the frequent gamma ray bursts which would destroy life.

Specialties

Fission

If one is to specialize in fission, one must study nuclear reactors, fission systems, and nuclear power plants, the primary teachings deal with neutronics and thermal-hydraulics for nuclear generated electricity. A firm foundation in thermodynamics and fluid mechanics in addition to hydrodynamics is a must. Nuclear engineers in this field generally work, directly or indirectly, in the nuclear power industry or for government labs. Current research in industry is directed at producing economical, proliferation resistent reactor designs with passive safety features. Although government labs research the same areas as industry, they also study a mirid of other issues such as: nuclear fuels and cycles, advanced reactor designs, and nuclear weapon design and maintainence.

Fusion

If one wants to specialize in nuclear fusion research, one would take several courses on electrodynamics and plasmas. This area is very much research oriented. Research areas include high-temperature, radiation-resistent materials, and plasma dynamics. Internationally, research is currently directed at building a prototype tokamak called ITER. The research at ITER will primarily focus on instabilities and diverter design refinement. Researchers in the USA are also building an inertial confinement experiment called the National Ignition Facility or NIF. NIF will be used to refine neutron transport calculations for the US stockpile stewardship innitative.

Nuclear medicine

If one wants to specialize in nuclear medicine, one would take courses dealing with doses and absorption of radiation in bodily tissues. Those who get competency in this area usually move into the medical field.