MCNP5 Calculations Replicating ARH-600 Nitrate Data

Technical Report · Wed Oct 26 00:00:00 EDT 2011

DOI:https://doi.org/10.2172/1047869· OSTI ID:1047869

Finfrock, S. H. ^[1]

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1. Hanford Site (HNF), Richland, WA (United States)

This report serves to extend the previous document: "MCNP Calculations Replicating ARH-600 Data" by replicating the nitrate curves found in ARH-600. This report includes the MCNP models used, the calculated critical dimension for each analyzed parameter set, and the resulting data libraries for use with the CritView code. As with the ARH-600 data, this report is not meant to replace the analysis of the fissile systems by qualified criticality personnel. The MCNP data is presented without accounting for the statistical uncertainty (although this is typically less than 0.001) or bias and, as such, the application of a reasonable safety margin is required. The data that follows pertains to the uranyl nitrate and plutonium nitrate spheres, infinite cylinders, and infinite slabs of varying isotopic composition, reflector thickness, and molarity. Each of the cases was modeled in MCNP (version 5.1.40), using the ENDF/B-VI cross section set. Given a molarity, isotopic composition, and reflector thickness, the fissile concentration and diameter (or thicknesses in the case of the slab geometries) were varied. The diameter for which k-effective equals 1.00 for a given concentration could then be calculated and graphed. These graphs are included in this report. The pages that follow describe the regions modeled, formulas for calculating the various parameters, a list of cross-sections used in the calculations, a description of the automation routine and data, and finally the data output. The data of most interest are the critical dimensions of the various systems analyzed. This is presented graphically, and in table format, in Appendix B. Appendix C provides a text listing of the same data in a format that is compatible with the CritView code. Appendices D and E provide listing of example Template files and MCNP input files (these are discussed further in Section 4). Appendix F is a complete listing of all of the output data (i.e., all of the analyzed dimensions and the resulting k_eff values).

• Research Organization: Hanford Site (HNF), Richland, WA (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA), Nuclear Criticality Safety Program (NCSP)
• DOE Contract Number: AC06-08RL14788
• OSTI ID: 1047869
• Report Number(s): CHPRC-01552-Rev-0; TRN: US201216%%721
• Country of Publication: United States
• Language: English

Related Subjects

97 MATHEMATICS AND COMPUTING
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
AUTOMATION
CRITICALITY
CROSS SECTIONS
DIMENSIONS
NITRATES
PERSONNEL
PLUTONIUM NITRATES
SAFETY MARGINS
THICKNESS
URANYL NITRATES
Nuclear Criticality Safety Program (NCSP)
Criticality
Cross Sections
k-eff
K-Effective
MCNP
Calculations
ARH-6-00
CritView Code