Use of hydrocode modeling to develop advanced MMOD shielding designs

A multi-physics computations-based methodology for space debris hypervelocity impact (HVI) damage mitigation is presented. Specifically, improved debris mitigation through development of innovative, lightweight structural designs is described. The methodology has been applied to the design of the Solar Probe Plus (SPP) spacecraft to mitigate extreme solar microdust hypervelocity impacts (50-300 km/s) by the Johns Hopkins University Applied Physics Laboratory (JHU/APL). The methodology combines hydrocode computations of the complex, early-time transient material and structural responses with experimental hypervelocity impact data to directly obtain end-state damage predictions for the requisite hypervelocities that are in excess of available test capabilities (~10 km/s). The computations are validated in the low-velocity regime (<;10 km/s) by direct HVI testing and verified in the high-velocity regime (50-300 km/s) by comparisons with bounding energy calculations and extrapolations of Ballistic Limit Equations (BLEs). In addition to hydrocode computations, HVI experimental data and supporting structural/solid mechanics analyses are used to define the eventual damage. In addition to being able to treat realistic hypervelocities and spacecraft materials in layered and Whipple configurations systematically, the methodology provides the margin of safety for any design. Sample lightweight design calculations involving state-of-art and innovative protective materials are presented to demonstrate the methodology and its benefits.