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3DHZETRN: Neutron leakage in finite objects
John W Wilson1, Tony C Slaba2, Francis F Badavi1
1Old Dominion University, Norfolk, VA 23529, USA.
Life Sciences in Space Research
|November 11, 2015
Summary
The 3DHZETRN code shows good agreement with Monte Carlo simulations for neutron transport. However, refining the neutron production approximation can improve leakage estimations in radiation transport modeling.
Area of Science:
- Nuclear Engineering
- Computational Physics
- Radiation Shielding
Background:
- The 3DHZETRN formalism extends HZETRN for 3D neutron and light ion transport.
- Previous comparisons validated 3DHZETRN against Monte Carlo (MC) simulations in simple geometries.
Purpose of the Study:
- To investigate discrepancies between transport codes and nuclear models.
- To study neutron leakage in finite objects using a defined leakage ratio.
- To assess the impact of approximations in neutron production cross-sections.
Main Methods:
- Combined existing and new transport model results for slab and spherical geometries.
- Utilized the Webber 1956 solar particle event as a source boundary condition.
- Defined a leakage ratio to quantify fractional neutron leakage relative to a semi-infinite slab.
Main Results:
- 3DHZETRN generally agrees with MC codes, but differences arise from distinct nuclear models.
- The leakage ratio effectively isolates effects of angular scattering and absorption.
- Observed discrepancies highlight the need for further development in transport codes and nuclear models.
Conclusions:
- The isotropic/straight-ahead approximation in 3DHZETRN can be improved for more accurate neutron leakage estimates.
- Further development is needed to resolve discrepancies between transport codes and nuclear models.
- Detailed descriptions of angular scattering are crucial for precise radiation transport simulations.
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