PE Nuclear Exam Preparation Module Program—Learning Objectives

Below is a listing of the learning objectives for each module in the program.

General Knowledge

Introduction to the Nuclear PE Exam

Registering for the Exam

Know how to register with your state board.
Know how to set up a MyNCEES account and register for the exam.
Discuss the date and format of the PE Exam in Nuclear Engineering.
Discuss appropriate reference materials and where they may be obtained.

Preparations for the Exam

Discuss how to prepare prior to taking the exam.
Discuss appropriate reference materials and what items can be brought to the exam.
Describe the exam check-in process and scoring issues.

General Information

Nuclear History

Give a brief history of the discovery of radioactivity, nuclear fission, nuclear weapons, and nuclear power.

Agencies, Regulators, and Professional Organizations (PDF only)

Become familiar with the various agencies, regulators, and professional organizations that are involved with the nuclear field.

Science Background

Introduction to Units (PDF only)

Appropriate units are needed to arrive at correct answers.
- Be consistent with the system of units (SI or USCS) used throughout the problem, for all the parts.
- Units can help you check your answers; e.g., if a question is asking for power and you obtain the result in the units of energy, you will want to check for errors.
- If you choose to convert the values in the question to a different system from what is given, be sure to convert back!

This topic also includes the following modules (PDFs only):

-Unit Conversions: Nuclear Physics and Basic Units

-Unit Conversions: Flow Calculations

-Unit Conversions: Energy and Power

-Constants and Units

Fundamentals of Nuclear Structure

Identify the parts of an atom.
Understand the difference between atom, element, and isotope.
Recognize the symbol for an isotope and understand the difference between atomic number (Z) and atomic mass (A).

Fundamental Particles

Describe the fundamental particles in nuclear engineering.
Understand the atomic mass unit and the relative masses of the fundamental particles.
Recognize photons and how they relate to the electromagnetic spectrum.

The Electron

Describe electron charge (negative) and importance for chemical bonding.
Describe the periodic table layout.
Describe the electron capture mechanism.

Waves and Particles

Understand the wave-particle duality of light and fundamental particles.

Relativity and Time Dilation

Understand the formulation of the Theory of Special Relativity.
Become familiar with the topic of time dilation, and be able to calculate observed time in different frames of reference.

Length Contraction

Understand length contraction and mass increase from an example of muon creation.
Identify the energy invariance relationship.
Determine which radiation types are affected by relativity effects in typical nuclear engineering situations.

Cerenkov Radiation

Familiarize yourself with Cerenkov radiation.
Understand the index of refraction and variables in the equation.
Calculate the threshold energy for Cerenkov radiation in a medium.

Specification Area 1 – Radiological Analysis and Consequences

Analysis

Chart of the Nuclides

Understand the arrangement of the chart.
Identify the types of entries and how they relate to the stability of the isotope.
Describe decay mechanisms of isotopes in relation to their location on the chart.
Understand the relationship of target and product for different bombardment reactions.

Atom Density Calculations, Part I

Describe atom density.
Calculate atom density with a variety of input parameters.

Atom Density Calculations, Part II

Calculate atom density with a variety of input parameters.

Atom Density Calculations, Part III

Describe atom density calculations for solution systems.

Nuclear Reactions

Understand the conservation laws used in nuclear reactions.
Identify particles involved in decay reactions.
Write and identify the parts to a nuclear reaction equation.

Binding Energy

Determine how to calculate the Q-value for a reaction.
Understand mass defect/binding energy and how to calculate it.
Identify important parts of and concepts related to the nuclear binding energy curve.

Threshold Energy

Determine how to calculate the threshold energy for an endothermic reaction.
Understand that theQ-value is not the same as the threshold energy, as momentum must be conserved.

Nuclear Stability and X-Rays

Identify that for stable isotopes, the ratio of neutrons to protons in the nucleus increases as the atomic number increases.
Understand that a nucleus in an excited state can undergo internal conversion or isomeric transition, and recognize the differences between the two.
Identify that the energy of an X-ray is the difference in binding energies of the two orbitals.
Understand that X-rays are characteristic of the atom from which they came.

Radioactive Decay

Radioactive Decay Overview

Understand the difference between radiation, radioactivity, and radioisotope.
Identify radioactive decay and de-excitation processes.
Describe half-life.
Become familiar with radioactive decay equations.

Alpha and Beta Decay

Define and understand the processes of alpha and beta decay.
Define and calculate the value of Q for alpha and beta decay.
Determine the energies of beta and gamma decay particles using the Chart of the Nuclides.

Positron Decay and Electron Capture

Define and understand the processes of positron decay and electron capture.
Calculate or determine Q for positron decay and electron capture.

Radioactive Decay

Understand radioactive decay and half-life.
Identify the relationship between half-life and the decay constant.
Familiarize yourself with the decay equation.

Activity and Decay Rate

Understand terminology associated with activity, specific activity, and decay rate.
Calculate the activity of a mass of a given isotope.
Familiarize yourself with the different units of activity and decay.

Decay Chains

Understand terminology associated with radioactive decay chains.
Identify the difference between secular and transient equilibrium.
Familiarize yourself with the Bateman equation.

Isotope Production and Decay Summary

Understand how radioisotopes are produced.
Familiarize yourself with the production rate and decay equations.
Recognize when production reaches saturation activity.
Review general concepts in activity and decay.

Energy Deposition

Interactions of Heavy Charged Particles

Understand that heavy charged particles lose energy through ionization events and travel in a straight path.
Identify the stopping power provides information on the energy loss per unit path for the particles.
Understand the behavior of the particles is characterized by β and F(β).
Recognize materials are characterized by the natural log of the mean ionization potential; the nuclear charge, Z; and the atomic mass number, A.

Ranges and Heavy Charged Particles

Understand mass stopping power and how it changes based on material.
Understand how ranges of heavy charged particles are calculated.
Determine ranges of heavy charged particles, such as alphas, based on the range of a proton of the same velocity.

Range of Alpha Particles

Determine the range of alpha particles in different materials.
Summarize the mechanisms of heavy charged particle interactions and corresponding range in different materials.

Interactions of Electrons

Understand the two main mechanisms of electron/ positron interactions:

-Excitation and ionization.

-Bremsstrahlung.

Identify the difference in radiation paths between an electron and an alpha particle.
Recognize how annihilation interactions occur and the characteristics of the interaction.

Stopping Power of Electrons

Understand what stopping power is for beta particles.
Identify the difference between collisional and radiative stopping power.
Recognize the relativistic and classical equations governing mass and energy.
Become familiar with the stopping power equation.

Bremsstrahlung

Define and understand what bremsstrahlung is.
Identify how the Z of a material and the incoming particle mass affect bremsstrahlung intensity.
Recognize the empirical formula for determining the ratio of radiative and collisional stopping powers.
Become familiar with the radiation yield equation.

Range of Electrons

Understand what equations are needed to determine the range of beta particles.
Become familiar with the Beta Range–Energy graph.
Understand tabulated data on electron interactions in water.

Range of Electrons Examples

Understand the use of the empirical range equations to determine the range of beta particles.
Identify and use the equations for determining the range of betas through layers of low-Z materials.

Interaction of Photons with Matter

Particle Interactions

Identify that for charged particles interacting with atomic electrons, two events are possible:
If enough energy is given to the electron, it will be separated from the atom, creating an ion pair.
If insufficient energy is available, then the electron will be excited and move to a different orbital.
Understand that in both interactions, the charged particle will lose energy, with the amount dependent on the mass of the charged particle.

Photon Interactions Overview

Recognize photon interactions and the three main types of interactions:

-Photoelectric effect

-Compton scattering

-Pair production

Understand the difference between ionizing and non-ionizing radiation.

Photoelectric Effect

Identify the discovery and history of photoelectric absorption.
Become familiar with the work function.
Understand the process of photoelectric absorption, including X-ray emission.

Compton Scattering

Understand the physics of Compton scattering.
Become familiar with the Compton scattering equation to calculate incident photon energy, final photon energy, and photon scattering angle.
Calculate the maximum kinetic energy transferred to an electron in a Compton scattering event.

Pair Production

Understand that pair production is a threshold reaction requiring at least a 1.022-MeV incoming photon to occur.
Understand that 1.022 MeV of energy is converted to create an electron–positron pair.
Identify that collision of the positron with an electron produces annihilation radiation in the form of two 0.511-MeV gammas.

Photon Interaction Coefficients

Identify the basic concepts of cross sections for photon interactions.
Understand the difference between linear and mass attenuation and mass absorption coefficients.
Recognize how photons are attenuated.

Measuring Attenuation Coefficients (Mu)

Understand attenuation coefficients and the effect of materials on a beam of photons.
Identify the difference between “narrow” and “broad” beam geometries.
Work through examples that calculate how many photons interact in a given material.

Photon Cross Sections

Understand photon cross sections and how the different physical processes contribute to the overall cross section.
Identify the difference between microscopic and macroscopic cross sections.
Calculate linear attenuation coefficients and cross sections for different processes.

Absorption Cross Sections

Understand how photons transfer energy to a medium.
Be familiar with the different absorption coefficients.
Explain the difference between kerma and absorbed dose.

Process Cross Sections

Understand the three major photon interactions and the energy dependence for the interaction types to occur.
Become familiar with the types of problems using different interaction coefficients, materials, and incident photon radiation.

Radiation Detection and Dosimetry

Radiation Detection

Describe the various methods of detecting radiation.
Identify the best detectors for alpha radiation, beta radiation, gamma radiation, and neutrons.

Ionization Chambers and Proportional Counters

Understand the basic principles of ionization chambers.
Identify the major components of a detector.
Recognize the different voltage regions and how they apply to different detector types.

Gas-Filled Counters

Identify how a gas-filled detector works.
Understand how the applied voltage of the detector is proportional to the amount of ion pairs produced.
Understand the different regions gas-filled counters operate in and the advantages/ disadvantages of operation in those regions.

Semiconductor Detectors

Understand the use of semiconductor detectors and the physics behind their function.
Recognize the difference between conductors, insulators, and semiconductors.
Identify energy resolution and full-width at half-maximum (FWHM).

Scintillation Detectors

Identify how scintillation detectors work and the components that make up the detector.
Understand the different types of scintillators and their performance capabilities.

Radiation Dosimetry

Understand the difference between absorbed dose, dose, radiation dose, dose equivalent, activity, and quality factor (definitions from 10 CFR 20.1003).
Identify the different units of radiation and understand the differences and application.
Recognize the relationship between exposure and dose.

Radiation Dosimetry Topics

Understand the Bragg–Gray Principle.
Calculate the average or effective energy of radiation.
Determine exposure from an internal source or point source.

Radiation Dosimetry Examples

Work through different radiation dosimetry examples.
Become familiar with the different types of dose calculations, including units and terminology.

Internal Dosimetry

Define internal dosimetry as the study of radioisotope transport, deposition, and dosing within the human body.
Identify intake routes and critical organs for various radioisotopes.
Understand that radioisotopes have both a chemical and a radiological behavior within the body.

Internal Half-Lives

Understand metabolic removal, radiological half-life, biological half-life, and effective half-life.
Calculate effective half-lives in different examples.

Annual Limit on Intake (ALI) and Derived Air Concentration (DAC)

Describe annual limit on intake (ALI) and derived air concentration (DAC).
Calculate the dose given the air sample results.

Dose Assessment and Personnel Safety

Biological Effects of Radiation

Describe how radiation interacts with the body and affects cells.
Discuss the time frame of exposure.
Identify total effects of radiation.

Threshold Dose

Describe how radiation exposure and overall dose relate to the effects identified.
Discuss the linear no-threshold hypothesis.

Dose Limits

Understand the similarities and differences between the dose rate limits of the U.S. Nuclear Regulatory Commission (NRC) and the U.S. Department of Energy (DOE).
Identify NRC and DOE definitions for different radiation controlled areas.
Calculate the effective dose and effective dose equivalent.

Dose Topics

Understand how the organ receiving a dose and the type of radiation affect total equivalent dose received and how this applies to the overall dose limit.
Identify the difference between organ dose and the equivalent whole-body dose.

Shielding

External Radiation Protection and Shielding

Describe the three basic principles of radiation protection.
Understand the inverse square law.
Become familiar with the health effects of different radiation types.
Identify the basic attenuation equation.

Geometry of Shielding

Describe the difference between good geometry and broad-beam geometry (sometimes referred to as poor geometry).
Understand the effects of good geometry and broad-beam geometry.
Identify what buildup is and how it applies to the attenuation equation.

Determination of Buildup Factors

Understand how to determine the buildup factor for a specific problem.
Practice linear interpolation.
Complete an example of shielding using buildup factors.

Shielding Analysis

Understand the basis of the 2.5 mR/hr exposure level.
Work through the processes of shielding problems.

Shielding Examples, Part I

Complete a shielding example problem using buildup factors and interpolation.

Shielding Examples, Part II

Work through a shielding example using multiple gamma energies.

Photon Shielding Principles

Identify general radiation shielding topics.
Understand and calculate the half-value and tenth-value layers.
Understand bremsstrahlung radiation.
Identify aspects required for shielding bremsstrahlung radiation.

Specification Area 2 – Nuclear Fuel Cycle

Nuclear Fuel Cycle Front End

Nuclear Fuel Cycle: Front End

To learn:

– the purpose of each component of the open nuclear fuel cycle.

– how to perform material balance problems.

– how to perform separative work problems.

– how to calculate the cost of enrichment.

Enrichment: Gaseous Diffusion

To learn:

– the physics of gaseous diffusion enrichment and the associated equations.

– the details of a gaseous diffusion plant.

Enrichment: Gaseous Centrifugation

To learn:

– the physics of gaseous centrifugation enrichment.

– how to calculate the separative capacity of a centrifuge.

– comparison of the efficiency and capabilities of diffusion enrichment and centrifugation enrichment.

Front End Examples

Review several example problems.

Fuel Design and Analysis

Depletion, Burnup, and Transmutation

Identify the general equation used in these calculations and define the specific variables.
Understand production and loss terms for fuel, target material, and fission products.
Calculate burnup of fuel for given reactor conditions.

Reactor Fuel Design

Discuss the importance of reactor fuel.
Identify the different fuel materials and their features.
Understand the characteristics of fuel performance.
Recognize the mechanisms of fuel growth and swelling.

Burnable Poisons

Describe a burnable poison and its use in a nuclear reactor.
Understand the advantages of burnable poisons, specifically fuel utilization and reactivity control.
Identify common burnable poison materials and designs.

Cladding

Discuss the functional requirements of cladding.
Identify the different cladding materials and their features.
Understand the neutronic properties of cladding.
Identify zirconium alloys and their capabilities.

Fuel Assembly Fabrication

Understand the steps in fabrication a fuel assembly, including

– fuel pellet production

– fuel rod production

– fuel assembly production.

Identify differences between PWR and BWR fuel assemblies.

Nuclear Fuel Cycle Back End

Classification of Radioactive Waste

Describe the sources of radioactive waste.
Define the five categories of radioactive waste.
Describe the classes of low-level radioactive waste.
Describe how each category of radioactive waste is to be disposed of.

Decay Heat from UNF

Describe why it is important to be able to determine the decay heat from used nuclear fuel (UNF).
Discuss the qualitative behavior of decay heat generation rate after reactor shutdown.
Calculate decay heat for various operating and shutdown scenarios.

UNF Spent Fuel Pools

Describe the storage options for used nuclear fuel (UNF).
Describe the safety requirements for UNF spent fuel pools.

UNF Dry Cask Storage

Identify the two types of dry cask storage.
Describe the requirements for an independent spent fuel storage installation (ISFSI).

Transportation of Radioactive Materials

Explain the role of the NRC, the DOT, and other agencies involved in the transportation of radioactive materials.
Identify the different types of packages used in transporting radioactive materials.
Define transport index (TI) and how it is applied to the transportation of radioactive materials.
Define a SARP and describe its contents.

Geologic Disposal of Radioactive Waste

Discuss the relationship between activity and toxicity of radioactive waste.
Describe the geologic disposal features and advantages of different types of geologic media.
Discuss the status of UNF disposal in the United States.
Describe Oklo and discuss its relevance to radioactive waste disposal.
Describe WIPP.

Specification Area 3 – Nuclear Systems and Components

Steam

Steam Properties

Define subcooled, saturated, and superheated as applied to the states of water found in a nuclear power plant.
Define quality as applied to a saturated water system.
Describe how changes in pressure allow a BWR to produce steam in the core while a PWR doesn’t.

Fluid Parameters

Describe the parameters provided in the PE Nuclear Reference Handbook for subcooled water.
Describe the parameters provided in the PE Nuclear Reference Handbook for saturated water and steam.
Describe the parameters provided in the PE Nuclear Reference Handbook for superheated steam.

Steam Tables Examples, Part I

Determine the parameters provided in the PE Nuclear Reference Handbook for subcooled water.
Determine the parameters provided in the PE Nuclear Reference Handbook for superheated steam.
Determine the condition of steam (saturated or superheated) and use the appropriate table.

Steam Tables Examples, Part II

Determine the quality for saturated steam-water mixtures when given a specific volume or enthalpy or entropy at a given condition.
Determine any or all of the parameters provided in the PE Nuclear Reference Handbook for saturated steam-water mixtures when given a quality at a given condition.

Steam Tables Examples, Part III

Determine the parameters provided in the PE Nuclear Reference Handbook for saturated steam-water mixtures when given a quality and temperature.
Calculate parameters using either English units or SI units commonly known as metric units.

Steam Tables Examples, Part IV

Using the steam tables, calculate the work done in a turbine based on given inlet and outlet conditions.
Using the turbine efficiency, calculate the actual work and the actual turbine outlet conditions.

Fluids

Fluid Flow and Energy Balance

Describe the relationship between Bernoulli’s equation and the First Law of Thermodynamics.
Discuss each of the terms in the general energy balance equation.
Given the initial and final conditions of the system, calculate the unknown fluid properties using the simplified Bernoulli equation.

Pressure Head

Define the term head with respect to its use in fluid flow.
Given a set of system conditions, calculate the pump head or friction head using the modified Bernoulli equation.

Laminar and Turbulent Flow

Describe the characteristics and flow velocity profiles of laminar flow and turbulent flow.
Define viscosity and how it varies with temperature.
Describe the relationship between the Reynolds number and the degree of turbulence of the flow.

Friction Factors

Define the four different friction factors and how they are related.
Discuss the relationship between friction factor and Reynolds number and how this is demonstrated on a Moody chart.

Determination of Friction Factor

Determine the value of the friction factor using the Moody Chart.
Describe how the roughness is related to pipe material.
Discuss how relative roughness is calculated and how it affects the friction factor.

Calculation of Friction Head

Determine the value of the friction head for a given set of fluid flow conditions.
Define fully developed turbulent flow and how this affects the friction factor.
Discuss how the friction head is related to change in velocity and to change in Reynolds number for fully developed turbulent flow.

Pumps

Pumps: Introduction

Define the suction and discharge sides of a pump and where the reference line for elevation is.
Calculate the hydraulic horsepower of a pump in terms of gpm and psi.
Calculate the brake horsepower of a pump given the pump efficiency and the head and pressure change in either SI or English units.

Pump Head and Calculations

Define the four different heads associated with a pumping system.
Identify the heads associated with static head and describe why they are “static.”
Define the total developed head and describe how it is used to create a manufacturer’s pump curve.

Pumps: Cavitation and NPSH

Define cavitation and how it affects pump operation.
State the equation for calculating NPSH_a and define each of the terms.
State the requirement for NPSH_a relative to NPSH_r for proper pump operation.
Discuss how the location of the fluid source with respect to pump centerline affects NPSH_a.

Pumps: Examples of NPSH Calculations

Calculate the NPSH_a for a given pump layout.
Calculate NPSH_r for a given pump suction head and system layout.
Determine minimum fluid level to avoid cavitation.

Pump Performance

List the five parameters used to specify a pump.
Describe how pump curves are used to indicate variation of head, efficiency, and bhp with flow rate.
Discuss how impeller size affects head.

Pump Operation

Describe how to create a system curve that gives the system head versus system flow rate.
Calculate the system dynamic head for a flow rate given the system dynamic head at another flow rate.
Identify the operating point from a given pump curve and system curve.
Discuss how valve operation affects flow rate and pump operating point.

Pump Calculations: Examples, Part I

Identify characteristics of pump curves.
Calculate pump discharge conditions.
Describe the effect of changes in valve conditions and/or pipe diameters on the system curve.

Pump Calculations: Examples, Part II

For a given system layout:

Calculate head for suction side.
Calculate head for discharge side.
Calculate static heads and total developed head (TDH).
Calculate NPSH_a for a given system.
Calculate hydraulic and brake horsepower.

Heat Exchangers

Heat Exchangers: Introduction

Describe how heat exchangers use fluid flow to exchange energy.
Identify where convective heat flow and where conductive heat flow is used in a heat exchanger.
Describe the arrangement that creates a double-pipe heat exchanger.
Define co-current and counter-current flow in a double-pipe heat exchanger.

Overall Heat Transfer Coefficient

State the equation for overall heat transfer rate in a heat exchanger and identify the factors.
State the equation for fluid content and show how it is related to overall heat transfer rate.
Define the overall heat transfer coefficient and describe how it is calculated using the sum of thermal resistances.
Define fouling and how it affects the overall heat transfer coefficient and overall heat transfer rate.
Define “clean” and “dirty” in relation to heat transfer rates in a heat exchanger.
Provide some typical values for fouling resistances.

Log Mean Temperature Difference

Define LMTD and describe its relationship to heat exchanger efficiency.
Calculate LMTD for a counter-current-flow heat exchanger.
Calculate LMTD for a co-current-flow heat exchanger.

Shell-and-Tube Heat Exchangers

Describe various components of a shell-and-tube heat exchanger.
Define the characteristics of a multipass shell-and-tube heat exchanger.
Identify some advantages and disadvantages of a multipass heat exchanger.
Discuss the importance of shell-side baffles.

Shell-and-Tube Heat Exchanger Parameters

Describe the various tube layouts commonly used in a shell-and-tube heat exchanger.
Define tube layout, tube pitch, tube counts, and shell diameter as applied to a shell-and-tube heat exchanger.
Define Prandtl number and Nusselt number.
Calculate Nusselt number using either the Dittus-Boelter or Sieder-Tate empirical equations.
Calculate a film coefficient from the Nusselt number.

Shell-and-Tube Heat Exchanger Example

Calculate heat transfer rate (HX duty).
Calculate inlet or outlet temperature of a fluid.
Calculate LMTD.
Calculate velocity; Reynolds number; Prandtl number; Nusselt number; and film coefficient, h, for fluid in the tubes.
Calculate outside surface area, A_o, and the overall heat transfer coefficient, U_o, for a shell-and-tube heat exchanger.

Shell-and-Tube Heat Exchanger Example Problems

Evaluate typical parameters applicable to heat exchangers and heat transfer.

Specification Area 4 – Reactor Physics and Criticality Safety

Kinetics

Delayed Neutrons

Describe the production of prompt and delayed neutrons through fission.
Describe the effect of delayed neutrons on the time behavior of a fissile system.
Define β_eff and what causes it to change in different systems containing the same fissile nuclides.

Reactivity and Period

Describe reactivity and the various ways it can be expressed.
Define the reactor period and how it relates to reactor power.
Define doubling time, halving time, and reactor startup rate and the relationships between these and the reactor period.

Point Kinetics and Prompt Behavior

Describe the impact of effective delayed neutrons on the time behavior of a system.
State the point kinetics equations and discuss the solution for one effective delayed neutron group.
Discuss the concept of prompt jump and prompt drop as related to positive and negative changes in system reactivity.
Describe the significance of the longest-lived delayed neutron group in system behavior for large negative reactivity changes.

System Time Behavior

Describe the time behavior for negative reactivity changes.
Describe the time behavior for small positive reactivity changes.
Describe the time behavior for large positive reactivity changes and the impact of the delayed neutron fraction.
Define the terms delayed critical, prompt critical, and prompt supercritical.
Describe the positive and negative feedback mechanisms that affect time behavior for large positive reactivity changes.
Describe the effects of overmoderation and undermoderation on system time behavior.

Kinetics Example Problems

Calculate the period, doubling/halving time, and/or SUR for a given reactivity change.
Calculate reactor conditions after a reactivity change.

Fission Product Poisoning

Describe how xenon poisoning affects reactor shutdown and startup.
Identify the typical flux value above which xenon poisoning is important in reactor startup.
Describe how samarium poisoning affects reactor operation, shutdown, and startup.
Describe the effects of fission products on absorption during reactor operation.
Discuss the impact of fission product poisoning on thermal and fast reactors.

Reactivity Coefficients and Transients

Describe why reactors are designed with negative moderator temperature coefficients.
Identify the two isotopes that dominate the Doppler effect in thermal reactors and describe how the effect depends on temperature.
Describe how xenon oscillations occur and their effect on reactor control.
Define ATWS and how consideration of such transients influences the design of reactors.

Neutronics and Criticality

Neutron Balance

Describe the four ways neutrons can interact in a fissile system.
Define critical, supercritical, and subcritical systems.
Define the infinite multiplication factor and the effective multiplication factor.
Define a reflector and provide examples.
Describe the neutron life cycle.

One-Group Diffusion theory

State the one-group diffusion equation and describe the interaction characterized by each of the terms.
Define the material buckling and geometric buckling and their relationship in critical, supercritical, and subcritical systems.
State the equation for the one-group infinite multiplication factor.
State the equation for the material buckling in a fast system.

Modified One-Group Diffusion Theory

Define the thermalization correction factors for fast leakage, fast fission, and resonance escape.
State the four- and six-factor formulas and describe the physical process represented by each term.
State the modified one-group diffusion equation and describe the interaction characterized by each of the terms.
Define the nonleakage probability.
Discuss the applicability and limitations of diffusion theory, one-group, and modified one-group.

Neutron Spectrum

Identify and describe the four regions of neutron energy.
Describe the characteristics of the fission spectrum.
Distinguish between a hard and a soft spectrum and describe how moderators are used to create a soft (thermal) spectrum.
Define the characteristics of a neutron moderator and give examples of typical moderating materials.
Define a thermal neutron and discuss how it is characterized by a Maxwellian distribution.
Describe the behavior of the neutron flux in the three main regions of a thermal reactor.
Describe the typical neutron energy spectra in a fast reactor and in a thermal reactor.

Neutron Cross Sections

Describe the different neutron interactions, the difference between elastic and inelastic scattering, and the difference between capture and fission events.
Define neutron cross sections and the factors that affect the probability of neutron interactions.
Distinguish between microscopic and macroscopic cross sections, and identify the units that apply to each.
Describe the effects of neutron energy on the probability of the four neutron interactions.
Discuss the cross-section behavior of a 1/v absorber as the neutron energy decreases from typical fission energies.

Neutron Cross Section Examples

Calculate interaction rate and interaction probability.
Calculate macroscopic cross sections for compounds.
Define mean-free-path and state how it is calculated for a compound.

Buckling Conversion

Describe the concept of buckling conversion and its use in determining equivalent critical geometries.
Discuss the impact of shape on the value of extrapolation distance for simple geometries.

Criticality Control

Identify the nine criticality parameters (MAGIC MERV).
Describe how the criticality parameters affect neutron production, absorption, and leakage—and hence, k-effective.
Identify those parameters that are dominant in fast systems and those that are dominant in slow (thermal) systems.
Define fast and thermal systems and how moderators and reflectors affect the neutron energy in each of these systems.

Criticality Example Problem

Describe the applicability of one-group and modified one-group diffusion theory to systems containing water or other moderators.
Discuss the need to correct 2200 m/sec fission and absorption cross sections for Maxwellian distribution, non-1/v behavior, and temperature effects.
Describe how to calculate critical slab thickness using modified one-group theory.

Nuclear Reactions and Q-values

Describe the four parameters that must be conserved in any nuclear reaction including radioactive decay.
Describe how to calculate the Q-value for any nuclear reaction using mass excess values.
Discuss the impact of the sign of the Q-value on the probability of a radioactive decay equation.

Nuclear Fission

Define high-Z materials as fissionable, fissile, threshold fissionable, or fertile.
Describe the fission process in terms of energy generated, particles produced, and the partitioning of the energy among the products.
Calculate the fission rate, rate of ²³⁵U consumption, and burnup.
Discuss the yield of fission products from fission.

Fission Products and Decay Heat

Describe the dominant decay process for fission products.
Discuss the qualitative behavior of decay heat generation rate after reactor shutdown.
Discuss the effect of burnup on the creation of actinide isotopes.
Describe how the presence of actinides impacts the decay heat generation rate.

Inverse Multiplication

Describe the concept of neutron multiplication as related to count rates from a detector and the effective multiplication factor of a system.
Describe the inverse multiplication approach for determining critical conditions.
Discuss the 75% rule and the 50% rule and their applications in approach-to-critical experiments.

Specification Area 5 – Safety Analysis

Note: This portion of the program is under construction. Users can find information on these topics in other study resources.

Design-Basis Analysis

Fuel Performance Analysis

Coming soon.

Pellet-Clad Interaction

Coming soon.

Core Thermal-Hydraulic Analysis

Coming soon.

Critical Heat Flux

Coming soon.

Departure from Nucleate Boiling

Coming soon.

LOCA Transient Analysis

Coming soon.

Long-Term Cooling

Coming soon.

Non-LOCA Transient Analysis

Coming soon.

Containment Performance

Coming soon.

Technical Specifications

Coming soon.

Safety Analysis Report

Coming soon.

Environmental Impact Statement

Coming soon.

Probabilistic Risk Assessment and Severe Accident Analysis

Probabilistic Risk Assessment: Introduction

Define risk assessment.
Define risk in terms of frequency and consequences.
Identify the three levels of PRA.
List three elements of a PRA.

Basic Concepts of Probability

Define what is meant by the probability of an event, the complement of an event, the union of two events, and the intersection of two events.
Define mutually independent events and mutually exclusive events.
Define conditional probability for two events.

Probability Operations

Define the rules of addition of probabilities for mutually exclusive and for non-mutually exclusive events.
Define the rules of multiplication of probabilities for mutually exclusive events, independent events, and dependent events.
Define the rule of subtraction for probabilities.

Probability Models

Describe the difference between combinations of items and permutations of subsets of those items.
Calculate numbers of combinations or permutations in a given set of items.
Identify how the binomial distribution is used in PRA analyses and use the equation to calculate probabilities.
Identify how the Poisson/exponential distribution is used in PRA analyses and use the equation to calculate system reliability.

Event and Fault Trees

Describe the difference between an event tree and a fault tree.
Discuss the relationship between the initiating event (IE) and the consequences.
Discuss the relationship between failure probabilities and the reliability of system equipment.

Fault Tree Example

Determine a fault tree for an upset in a given operation.
Using Boolean operations, determine the probabilities for combinations of events.
Calculate the frequency of an upset event.

PRA Example Problems

Use the binomial distribution to calculate probability of r failures in N trials.
Use concepts of Boolean algebra to calculate the probability of independent failures.
Calculate the probability of a sequence of events using conditional probability.
Calculate the probability of failure to start for systems with common-cause failures.
Define the mean time to failure (MTTF) and how it relates to the reliability of a system.
Calculate the probability of failure to run for different time periods given the MTTF.

Uncertainty Analysis