Passive Space Radiation Shielding: Mass and Volume Optimization of Tungsten-Doped PolyPhenolic and Polyethylene Resins

The use of commercial, off-the-shelf (COTS) components have become an increasingly attractive option to develop small satellites that satisfy high-quality and reliability, as well as low-cost and development time demands. However, the use of COTS may introduce mission design constraints associated with the mass and volume of appropriate radiation shielding required for various mission lifetime and/or reliability objectives. The purpose of this study is to provide insights towards optimization that minimizes the mass and/or volume of a graded-Z or composite-Z shield. In this study, three model space radiation environments will be attenuated via mass shields using numerical analysis, with a discussion provided on the manufacturability and integration of such shields within the small sat design envelope. The use of graded-Z shielding for multi-particle attenuation is not a new concept. However, as this area of application is yet emerging, few concepts have the development maturity at a Technology Readiness Level of three (TRL-3). Previous design approaches employed an optimization strategy that equally weighed the structural ability of the given system equally against its shielding performance. The current study removes the specific structural constraint, and examines the mass associated with a constant thickness Tungsten-doped PolyPhenolic and Polyethylene resins.