The objective of this research is to design a portable neutron detector that is lightweight and responds to neutrons with energies of 20 MeV and greater. The instrument will be used as a ‘sniffer’ probe for identifying shielding weaknesses at high-energy particle accelerators and be paired with a plastic scintillator...
This thesis presents and discusses a method for comparing
the neutron flux of some calculational model with the actual
flux of a critical system. Both the theoretical and experimental
aspects of this method are investigated in this report.
Experiments were performed to find neutron energy dependent
data. These involved the...
A standard fast reactor spectrum can be created by the partial moderation of the U-235 fission spectrum in an air cavity. Spherical natural uranium shells are driven by thermal neutrons from a thermal column. The uranium is placed at the center of a spherical graphite hohlraum to reduce the anisotropic...
Verification of fast reactor safety requires experiments
wherein fuel bundles, enclosed in massive steel capsules, are subjected
to simulated accident conditions in reactors such as TREAT(16)
at ANL Idaho. To date, only small bundles (one to seven pins) have
been tested in the experimental series. Determination of the fuel
configuration...
A system to perform neutron radiographic analysis of dynamic
events taking place over the order of several milliseconds has been
developed at Oregon State University. The design consists of a TRIGA
reactor capable of pulsing to 3000 MW peak power, a neutron beam
collimator with an L/D of about 30:1,...
Current research in the area of two-phase flow utilizes
a wide variety of sensing devices, but some limitations exist
on the information which can be obtained. Neutron radiography
is a feasible alternative to "see" the two-phase flow.
A system to perform neutron radiographic analysis of dynamic
events which occur on...
A high speed motion neutron radiography system has been developed
at Oregon State University which is capable of taking high speed
neutron radiographs of events which occur on the order of one to two
milliseconds or more. This system was used previously to demonstrate
the application of high speed motion...
A facility developed using the OSU TRIGA pulsing capability and high speed motion photography has been used successfully for more than a decade to produce dynamic neutron radiographs of solid propellant combustion, two phase flow, and liquid streamflow. The existing imaging components have undergone little modification since the experiment's inception...
A real-time neutron radiography system has been
developed at Oregon State University which is capable of
producing neutron radiographs of objects and events
concurrent with the incident radiation. The purpose of
this thesis is to demonstrate the feasibility of the
real-time technique as a further application of neutron
radiography at...
Spatial flux profiles were calculated in idealized,
optically-thin ( 1 mfp) cell systems using integral
transport theory. Numerical accuracy improvement and
convergence efficiency in computing these spatial flux
profiles was the primary concern. Toward these ends, kernel
volume-averaging techniques for curvilinear cell systems, a
reflective angular-dependent edge source boundary condition...
The objective of this work was to determine and optimize the resolution of a neutron sensitive Multi-Channel Plate (MCP) detector in order to determine its capabilities in radiography and tomography. The Oregon State University, Neutron Radiography Facility added an MCP Detector in 2012 in order to analyze these capabilities. The...
Soil moisture in a crop's root zone must be regularly
monitored to accurately predict crop water requirements.
Most irrigation scheduling services currently
use the neutron probe to monitor soil moisture. Unfortunately,
there is a degree of variability associated
with use of the neutron probe creating uncertainty in
measurements of soil...
There exists a variety of methods to solve the radiation transport equation in stochastic materials, including the Levermore-Pomraning method and the atomic mix method, each of which is designed to replicate the results given by benchmarks with materials rearranged in a randomized fashion. While the atomic mix method is very...