NEEP 405 Homework Set # 12
1. Briefly explain why a too large chemical shim concentration in the coolant could
potentially lead to a positive temperature feedback coefficient.
2. D&H 14-9
3. D&H 14-12 (Probably the most difficult problem. You have to firs
Homework Set # 11
1. Derive the Point Reactor Kinetics Equations. Follow the discussion in the notes or
book but complete all intermediate steps.
2. Write a short treatise on the prompt jump approximationfound in Chapter 6.
3. Compare the fractio
NEEP 405 Homework Set # 10
1. 8-23 [do only for 500 C]
3. Using the Matlab script provided on the course home page, compute the thermal
spectra for 235U and 239Pu. This will involve modeling the absorption cross
sections for each of these in the
NEEP 405 Homework Set # 9
D&H 8-2(a) Use the fission spectrum from Chapter 2 as the source S(E).
Starting with a 1 keV source of neutrons, compute the energy group boundaries
that ensure that neutrons downscatter in
NEEP 405 Homework Set # 8
1. (2 points) D&H 7-11
2. (3 points) D&H 7-14
3. (5 points) Consider the following situation. You have a unit fuel cell with UO2
fuel surrounded with H2O moderator. The fuel pin diameter is 0.94 cm and the
unit cell pitch is 1.25
NEEP 405 Homework Set # 7
1. D&H 5-30 In a real reactor we want the power peaking factor to be as close to
one as possible. This is because the fission rate is proportional to the flux so the
heat generation rate is highest where the flux is highest. But
NEEP 405 Homework Set # 6
15 points, each problem is 7.5 points
1. Consider a finite slab of Aluminum from x=0 to x=a. On the left face of the slab
there is a beam of thermal neutrons incident with intensity I0. The beam of
incident neutrons is only margi
NEEP 405 Homework Set # 5
1. D&H 5-3 Derive the root mean square distance
a neutron will travel
from a plane source to absorption in an infinite medium using one-speed diffusion
theory. What is the rms distance to absorption for a plane source in
NEEP 405 Homework Set # 4
1) The neutron continuity equation is derived in the text using the integral form concept.
In other words a macroscopic volume is considered and an integral over the volume
involving the scalar flux is related to an integral over
NEEP 405 Homework Set # 3
1. D&H 3-6 [Assume that the 238U-235U is mixed 1:1000 with water to ensure that
there is a thermal neutron spectrum and the thermal cross sections in Appendix A
are valid.] Can natural U be mixed with water to produce a critical
NEEP 405 Homework Set # 2
1. A thickness of 143.9 cm is required to attenuate a thermal neutron beam to 0.1%
of its initial intensity. What material is being used? (Use Appendix A for total
cross section data.)
2. Suppose a shield that is infinite in the
NEEP 405 Homework Set # 1
1. D&H problem 2-1.
2. D&H problem 2-2.
3. D&H problem 2-3 Work this problem for 4 isotopes N1(t), N2(t), N3(t), and N4(t).
The initial concentration of N1(t) is N1(0)=N1init and the initial concentration of the
other isotopes is