Accession Number : AD1051626


Title :   Special Features of the Air-to Space Neutron Transport Problem


Descriptive Note : Technical Report,01 Oct 2014,30 Sep 2017


Corporate Author : AIR FORCE INSTITUTE OF TECHNOLOGY WRIGHT-PATTERSON AFB OH WRIGHT-PATTERSON AFB United States


Personal Author(s) : Dailey, Whitman T


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/1051626.pdf


Report Date : 14 Sep 2017


Pagination or Media Count : 223


Abstract : Special features of the air-to-space neutron transport problem are identified, characterized, and quantified to provide information on features that should be included in Monte Carlo simulations to obtain accurate predictions. Currently available codes and tools for Monte Carlo neutron transport calculations do not provide an adequate (in accuracy nor precision nor efficiency) framework for practical transport calculations in the context of the air-to-space neutron transport problem. A new Fortran code, High Altitude Transport to Space for Neutrons (HATS-n), is developed and tested to perform high fidelity Monte Carlo neutron transport calculations for this class of problems. Special features of the air-to-space neutron transport are identified and categorized: The influence of relative motions, the influence of gravity, the influence of the implementation of the atmosphere model, and the influence of radioactive decay of free neutrons. Each special feature is examined individually and methods and procedures are developed for research and practical implementations. Finally, the features are demonstrated in concert using the new HATS-n code.


Descriptors :   algorithms , altitude , artificial satellites , accuracy , atmospheric temperature , estimators , high altitude , kinetic energy , apogees , monte carlo method , geometry , geosynchronous orbits , computational science


Subject Categories : Statistics and Probability


Distribution Statement : APPROVED FOR PUBLIC RELEASE