A space radiation transport method development.

J W Wilson; R K Tripathi; G D Qualls; F A Cucinotta; R E Prael; J W Norbury; J H Heinbockel; J Tweed

doi:10.1016/j.asr.2003.10.048

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A space radiation transport method development.

J W Wilson·R K Tripathi·G D Qualls·F A Cucinotta·R E Prael·J W Norbury·J H Heinbockel·J Tweed

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Abstract

Improved spacecraft shield design requires early entry of radiation constraints into the design process to maximize performance and minimize costs. As a result, we have been investigating high-speed computational procedures to allow shield analysis from the preliminary design concepts to the final design. In particular, we will discuss the progress towards a full three-dimensional and computationally efficient deterministic code for which the current HZETRN evaluates the lowest-order asymptotic term. HZETRN is the first deterministic solution to the Boltzmann equation allowing field mapping within the International Space Station (ISS) in tens of minutes using standard finite element method (FEM) geometry common to engineering design practice enabling development of integrated multidisciplinary design optimization methods. A single ray trace in ISS FEM geometry requires 14 ms and severely limits application of Monte Carlo methods to such engineering models. A potential means of improving the Monte Carlo efficiency in coupling to spacecraft geometry is given in terms of re-configurable computing and could be utilized in the final design as verification of the deterministic method optimized design.

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Cosmids Databases, Factual Equipment Design Facility Design and Construction Finite Element Analysis Heavy Ions Linear Energy Transfer Mathematics Models, Theoretical Monte Carlo Method Neutrons Radiation Protection Space Flight Spacecraft NASA Center JSC NASA Center LaRC NASA Discipline Radiation Health Journal Article

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J W Wilson, R K Tripathi, G D Qualls, F A Cucinotta, R E Prael, J W Norbury, J H Heinbockel, J Tweed. 2004. A space radiation transport method development.. https://doi.org/10.1016/j.asr.2003.10.048

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