NUCLEAR REACTOR THEORY
Course objectives
The objective of the course is to provide a general comprehension of the physical phenomena underlying the slowing-down and diffusion/transport of neutrons in media without and with nuclear fuel, and to illustrate the mathematical tools necessary to carry out criticality calculations. As a learning outcome, the student is expected to be able to perform and interpret analytical calculations relative to the neutronic design of a nuclear reactor, both in static and dynamic conditions.
Channel 1
RENATO GATTO
Lecturers' profile
Program - Frequency - Exams
Course program
1. Introduction to reactor physics
2. Mean free path
3. Fick’s law and diffusion equation
4. Slowing down of neutrons
4.1 Elastic scattering
4.2 Scattering law
4.3 Mean logarithmic decrement
4.4 Slowing down power and moderation ratio
4.5 Lethargy
5. Slowing-down in infinite, non-absorbing media
5.1 Slowing-down in hydrogen
5.2 Slowing-down density in hydrogen
5.3 Slowing-down in media containing media with atomic mass greater than one
5.4 Slowing-down in a system containing different nuclides
6. Slowing-down in infinite absorbing media
6.1 Slowing-down with capture in hydrogen moderator. Resonance escape probability
6.2 Slowing-down in media containing nuclei with atomic mass greater than one
6.3 Resonance escape probability with well-separated resonances
7. Neutron diffusion (basic transport approximation)
7.1 Transport correction
7.2 Transport mean free path
7.3 Diffusion equation
7.4 Boundary conditions
7.5 Solutions of the diffusion equation
7.6 Point-like source in an infinite media
7.7 Infinite plain source
7.8 Infinite plain source in a media of finite thickness
7.9 Plain source with two slabs of finite thickness
7.10 Diffusion length
7.11 Albedo
8. Neutron “age” theory
8.1 Continuous slowing-down model
8.2 “Age” equation without captures
9. The homogeneous thermal reactor without reflector
9.1 Crtical equation
9.2 Approach to criticality
9.3 Criticality condition
9.4 Material and geometric buckling
9.5 Generation time
9.6 Reactors with different geometries
9.6.1 Infinite slab
9.6.2 Rectangular parallelepiped
9.6.3 Sphere
9.6.4 Finite cylinder
10. Subcritical multiplication
11. The homogeneous reactor with reflector
11.1 One group of neutrons
11.2 Infinite plane slab
11.3 Reflector savings
11.4 The ratio between maximum and average flux in a slab reactor
11.5 Two groups of neutrons
12. Transport equation
12.1 Transport theory
12.2 Transport kinetic equation
13. Transport approximations (more sophisticated approximations)
13.1 “Pn” approximation
13.2 Multigroup approximation
14. Multigroup libraries
14.1 The “variable” library. Power iteration method.
14.2 The “ABBN” library
15 Kinetic equation
15.1 The inhour equation
15.2 Solution with one precursor family
16 Reactivity coefficients (p, f , PN L )
17 Nonlinear reactor dynamics
18 Poisoning due to fission products
18.1 Poisoning due to Xenon
18.2 Poisoning due to Samarium
19 Burnup and fuel cycle
20 Heterogeneous reactor
20.1 Microscopic reactor physics (K factor)
20.1 Macroscopic reactor physics
21 Perturbation theory (optional)
21.1 Adjoint flux
21.2 Perturbative formulation of reactivity
Prerequisites
1st level degree in Engineering or Physics.
Books
"The elements of nuclear reactor theory" by Glasstone and Edlund.
Lecture notes distributed by the Instructor.
Exam mode
Assessment of the student's ability to describe qualitatively (in words) and quantitatively (with mathematical formulas) the physical phenomena underlying neutronincs applied to the nuclear fission reactor core. The student will also be expected to present and comment on the results of the assigned project, demonstrating mastery of the mathematical and numerical procedures used.
- Lesson code1052120
- Academic year2024/2025
- CourseEnergy Engineering
- CurriculumScienze e tecnologie nucleari
- Year1st year
- Semester2nd semester
- SSDING-IND/19
- CFU9
- Subject areaIngegneria energetica e nucleare