MMOD impact of pressurized vessels: Review of design criteria and response prediction equations

Most spacecraft have at least one pressurized vessel on board. For robotic spacecraft, it is usually a liquid propellant tank or battery. Manned spacecraft use these elements as well, and there are also pressurized living quarters and life-support systems. One of the design considerations of such spacecraft is the possible damage that might occur in the event of an on-orbit impact by a micro-meteoroid or orbital debris (MMOD) particle. While considerable energy and effort has been expended in the study of the response of non-pressurized spacecraft components to these kinds of impacts, relatively few studies have been conducted on the pressurized elements of such spacecraft. In addition, the design criteria currently used by NASA for pressurized tanks operating in the MMOD environment have not been tested or scrutinized since they were first proposed nearly 50 years ago. In this paper we review current NASA design criteria for pressurized vessels and offer suggestions for next steps in their development. We also review the development of rupture limit equations that can be used to differentiate between impact conditions that would result in only a small hole or crack in a pressurized tank, from those that would cause catastrophic tank failure. This information would be useful to a design engineer who might be able to select tank materials and tailor operating conditions to avoid catastrophic tank failure in the event of a perforating on-orbit MMOD particle impact.