ME455-655Fa21HW-4
.docx
School
University of Nevada, Las Vegas**We aren't endorsed by this school
Course
ME 455
Subject
Mechanical Engineering
Date
Dec 16, 2024
Pages
1
Uploaded by dennismitche10
Student Name ____________________________________ ME 455/655 Fundamentals of Nuclear Engineering Fall 2021 Homework 4 Problem 1:The reactor on the nuclear ship “Savannah” operated at a power of 69 MW. (a)How much 235U was consumed on a 10000-nautical-milevoyage at an average speed of 20 knots? (b)This is equivalent to how manybarrelsof 6.5-million-Btu/barrelbunker-C oil? Problem 2:The photoelectric cross-section of leadat 0.6 MeVis ~18 b. Estimate peat thisenergy for uranium. Problem 3:A research reactor is operated at a power of 250 kilowattsfor 2 years. A fuelelement, 1 of 24 in the reactor, is then removed for examination. Compute and plotthe activityof the fuel elementas a functionof timeup to 2 yearsafter removal. Problem 4:Two hypothetical nuclei, AZand A+1Z, of atomic weights M(AZ) = 241.0600 and M(A+1Z)= 242.0621 have critical fission energies of 5.5 MeVand 6.5 MeV, respectively. Is the nuclide AZfissile? Problem 5:The density of air at standard temperature and pressure (0C and 1 atm) is1.293×10-3g/cm3. Compute the mean free pathsof photonsin airunder these conditions andcompare with the corresponding mean free paths in unit-density waterat the followingenergies: (a)0.1 MeV; (b)1 MeV; (c)10 MeV.
