Wisconsin Institute of Nuclear Systems (WINS)Research, education, and public service related to technical issues of nuclear systems with specific emphasis on advanced nuclear energy applicationshttp://digital.library.wisc.edu/1793/3252024-03-28T23:20:34Z2024-03-28T23:20:34ZNeutron/Gamma Mixed Spectrum Radiolysis-based Aqueous DosimetrySetter, Timothyhttp://digital.library.wisc.edu/1793/622772019-04-24T14:10:12Z2007-01-01T00:00:00ZNeutron/Gamma Mixed Spectrum Radiolysis-based Aqueous Dosimetry
Setter, Timothy
This work develops a method to use an aqueous dosimeter in a mixed radiation field to determine separate measurements of neutron and gamma dose. Based on radiolysis of both Fricke and Methyl Viologen (MV) solutions, activation analysis and reactor simulation are combined to determine neutron dose and neutron radiolysis. This is subtracted from the total measured radiolysis to infer a gamma dose. The Fricke dosimeter was able to give repeatable results for the neutron and gamma doses over a number of days for a variety of shielding configurations. Impurities in the MV dosimeter prevented it from providing repeatable results, but qualitative comparison to the Fricke dosimeter indicated that it could be a viable approach. The method found that the reactor simulation, using MCNP5, can be used for accurate neutron simulations but does not account for all the source terms for gamma dose simulation. A neutron G-value for the Fricke dosimeter was developed by combining proton radiolysis simulations with results from MCNP5 and NJOY.
2007-01-01T00:00:00ZDetermination of Pure Neutron Radiolysis Yields for use in Chemical Modeling of Supercritical WaterEdwards, Erichttp://digital.library.wisc.edu/1793/622732019-04-24T14:10:12Z2007-01-01T00:00:00ZDetermination of Pure Neutron Radiolysis Yields for use in Chemical Modeling of Supercritical Water
Edwards, Eric
This work has determined pure neutron radical yields at elevated temperature and pressure up to supercritical conditions using a reactor core radiation. The data will be necessary to provides realistic conditions for material corrosion experiments for the supercritical water reactor (SCWR) through water chemistry modeling. The work has been performed at the University of Wisconsin Nuclear Reactor using an apparatus designed to transport supercritical water near the reactor core. Low LET yield data used in the experiment was provided by a similar project at the Notre Dame Radiation Lab.
Radicals formed by radiolysis were measured through chemical scavenging reactions. The aqueous electron was measured by two methods, a reaction with N2O to produce molecular nitrogen and a reaction with SF6 to produce fluoride ions. The hydrogen radical was measured through a reaction with ethanol-D6 (CD3CD2OD) to form HD. Molecular hydrogen was measured directly. Gaseous products were measured with a mass spectrometer and ions were measured with an ion selective electrode. Radiation energy deposition was calibrated for neutron and gamma radiation separately with a neutron activation analysis and a radiolysis experiment. Pure neutron yields were calculated by subtracting gamma contribution using the calibrated gamma energy deposition and yield results from work at the Notre Dame Radiation Laboratory.
Pure neutron yields have been experimentally determined for aqueous electrons from 25o to 400o�C at 248 bar and for the hydrogen radical from 25o�C to 350o�C at 248�bar. Isothermal data has been acquired for the aqueous electron at 380o�C�and 400o C as a function of density. Molecular hydrogen yields were measured as a function of temperature and pressure, although there was evidence that chemical reactions with the walls of the water tubing were creating molecular hydrogen in addition to that formed through radiolysis. Critical hydrogen concentration behavior was investigated but a final result was not determined because a measurable oxygen yield was not seen at the outlet of the radiolysis loop.
2007-01-01T00:00:00ZDirect Use of CAD Geometry in Monte Carlo Radiation TransportWilson, Paul P.H.http://digital.library.wisc.edu/1793/612772019-04-24T14:10:03Z2012-03-27T00:00:00ZDirect Use of CAD Geometry in Monte Carlo Radiation Transport
Wilson, Paul P.H.
A comprehensive overview of the status of the Direct Accelerated Geometry for Monte Carlo (DAGMC) toolkit, including the fundamental components of the interface, the emerging set of performance obstacles and guarantees, and examples of analysis.
2012-03-27T00:00:00ZNuclear Energy: Current Trends,the Next Decade, and Beyond!Wilson, Paul P.H.http://digital.library.wisc.edu/1793/460782019-04-24T14:10:35Z2008-10-24T00:00:00ZNuclear Energy: Current Trends,the Next Decade, and Beyond!
Wilson, Paul P.H.
This presentation is an abbreviated October 2008 version of similar presentations given by Wilson over the last few years. It documents the last 10 years of continuous improvement in the nuclear energy industry leading to high capacity factors and low production costs. It then discusses the current status of new construction of nuclear power plants, given the current state of the energy industry, the economy and the related politics. It closes on a discussion of advanced fuel cycles and the drivers of reduced waste, increased resource utilization and improved proliferation resistance. Shorter than other versions, this one is designed to be about 30 minutes.
2008-10-24T00:00:00Z