Hypervelocity impact testing of a pressurized composite overwrapped pressure vessel and comparison to numerical analysis

As the outlook for space exploration becomes more ambitious and spacecraft travel deeper into space, it is increasingly important that systems with energetic material storage perform reliably within the space environment. Because hardware mass is limited, the use of high strength-to-weight Composite Overwrap Pressure Vessels (COPV) has enabled designers to store energy at a reduced mass penalty; however, because the composite overwrap carries a high fraction of the stress of pressurization, there is significant concern that damage to the composite overwrap can lead to vessel failure and potentially cause loss-of-vehicle/loss-of-crew. One of the greatest external threats to the integrity of a spacecraft's COPV is an impact from the meteoroid and orbital debris environments (MMOD). Because the limited research regarding this problem cannot be generalized, the capacity for these vessels to tolerate such impacts is not well understood. This report details some of the early experimental efforts undertaken by the Hypervelocity Impact Technology (HVIT) group in the support of a NASA Engineering and Safety Center (NESC) assessment to understand how hypervelocity impact conditions comparable to MMOD impacts initiate catastrophic COPV failure. In addition to this experimental work, this publication also reports on the development of a numerical method to guide the interpretation of the experimental data and extension to other flight relevant configurations.