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NE 256M

Course Title: 
Nuclear Criticality Safety
Course Units: 
Catalog Description: 

This course provides an introduction to the field of nuclear criticality safety. Topics covered include: a review of basic concepts related to criticality (fission, cross sections, multiplication factor, etc.); criticality safety accidents; standards applicable to criticality safety; hand calculations and Monte Carlo methods used in criticality safety analysis; criticality safety evaluation documents. 

Course Prerequisite: 

NE 150 or consent of instructor. 

Prerequisite Knowledge and/or Skills: 

The course uses the following knowledge and skills from prerequisite and lower-division courses: 
◦ Neutron interactions, cross sections; 
◦ Multiplication factor, reactivity; 
◦ Neutron flux, current; 
◦ Solution of linear, first and second order differential equations; 
​◦ Vector calculus, special functions (Bessel functions, exponential integrals). 

Course Objectives: 

The objective of this course is to acquaint Nuclear Engineering students with the concepts and practice of nuclear criticality safety, and to help prepare them for a future career in this field. 

Course Outcomes: 

At the end of this course, students should be able to:
◦ Explain and define criticality safety factors for operations.
◦ Discuss previous criticality accidents and their causal factors, including parameters involved in solution and metal critical accidents.
◦ Identify and discuss the application of several common hand calculation methods.
◦ Describe the importance of validation of computer codes and how it is accomplished.
◦ Discuss ANSI/ANS criticality safety regulations.
◦ Describe DOE regulations and practices in the nuclear criticality safety field.
◦ Complete a Criticality Safety Evaluation.

Topics Covered: 

Topics covered by week:

​◦ Review of neutron interactions, multiplication factor, reactivity
​◦ Factors in criticality safety: MAGICMERV/MERMAIDS
​◦ Criticality accidents
​◦ Criticality experiments
​◦ Criticality safety evaluation documents
​◦ Hand calculations: One-group and modified one-group diffsion theory
​◦ Hand calculations: methods review
​◦ Monte Carlo code: Intro
​◦ ANSI/ANS Standards (SD130)
​◦ DOE 10 CFR 820 and 420.1C
​◦ Criticality safety at national laboratories
​◦ Criticality safety evaluation presentation
​◦ RRR

Textbook(s) and/or Other Required Materials: 

R. A. Knief. Nuclear Criticality Safety: Theory and Practice. American Nuclear Society, 1985.

Additional references:
◦ J. Eric Lynn. Modern Fission Theory for Criticality. LA-14098.
◦ Douglas G. Bowen and Robert D. Busch. Hand Calculation Methods for Criticality Safety – A Primer. LA-14244-M.
◦ Thomas P. McLaughlin, Shean P. Monahan, and Norman L. Pruvost. A Review of Criticality Accidents (2000 Revision). LA-13638.
◦ D. L. Smith. Probability, Statistics, and Data Uncertainties in Nuclear Science and Technology. In OECD NEA Nuclear Data Committee Series “Neutron Physics and Nuclear Data in Science and Technology,” Vol. 4, American Nuclear Society, 1991
◦ Reference Values for Nuclear Criticality Safety. NEA 5433, 2006, Organization for Economic Co-Operation & Development (ISBN 92-64- 02333-X),

Class/Laboratory Schedule: 

The course consists of three hours of lecture per week. Some lectures will be delivered by criticality safety experts from a national laboratory.

Course Assignments and Grading: 

In order to successfully complete the course, students are required to complete:
◦ a weekly reading assignment;
◦ a weekly homework;
◦ a midterm (around week 8);
◦ a final project consisting in performing a criticality evaluation and compiling a criticality safety evaluation document.
The final grade will be calculated as follows:
◦ Homework: 30% (lowest grade dropped)
◦ Midterm: 40%
◦ Criticality safety evaluation: 30%
          – 15% presentation;
          – 15% document.
Grading scale (tentative): A+ >95%, A >91%, A- >87%, B+ >83%, B >79%, B- >75%, C+ >71%, C >67%, D >59%, F ≤59%