This thesis covers two topics. The first subject
involves tests run on a ultralite reflux tube supplied by
Battelle Pacific Northwest Laboratories (PNL). The second
topic involves tests to determine the relative wicking rates
of several different fabrics.
The ultralite reflux tube supplied by PNL was
constructed of copper and...
Five Ultra light Fabric Reflux Tubes (UFRTs) were tested in a thermal vacuum chamber at the National Aeronautics and Space Administration's Johnson Space Center in September 1994. These test articles were design and fabricated by staff at the Pacific Northwest Laboratory, operated by Battelle Memorial Institute for the United States...
The ion implantation process is a very precise, controllable, and
reproducible method used to enhance material properties of finished
components such as ball bearings. Essentially, the target material is
bombarded by accelerated ions to form a thin alloyed layer in the
substrate. As the ions deposit their kinetic energy in...
Incore thermionic space reactor design concepts which operate at a
nominal power output range of 20 to 50 kWe are described. Details of the
neutronic, thermionic, thermal hydraulics and shielding performance are
presented. Due to the strong absorption of thermal neutrons by natural
tungsten, and the large amount of that...
Preliminary nuclear design studies have been completed on ten
configurations of nuclear reactors for low power (1-30 kWe) space
applications utilizing thermionic energy conversion. Additional design
studies have been conducted on the TRICE multimegawatt in-core
thermionic reactor configuration. In each of the cases, a reactor
configuration has been determined which...
Lattice bum-up calculations in thermal reactors are complicated by the necessity
for use of transport theory to represent fuel rods, control rods, and burnable absorbers,
by many time-dependent variables which must be considered in the analysis, and by
geometric complexity which introduces time-dependent, spatial-spectral variations.
Representation of lattice structure in...
A transient code (TFETC) for calculating the temperature
distribution throughout the radial and axial positions of a
thermionic fuel element (TFE) has been successfully developed.
It accommodates the variations of temperatures, thermal power,
electrical power, voltage, and current density throughout the
TFE as a function of time as well as...
Safety concerns at the Hanford Reservation require a way to measure the
moisture content of material contained in the high level radioactive waste tanks. The
freezing of material next to a probe was proposed by scientists at Pacific Northwest
Laboratories (PNL) as one approach to solve this problem. It was...