Current U.S. Navy criteria to assess non‐auditory physiological impacts of explosives on marine mammalsrelies on limited datasets derived from past experiments using small submerged terrestrial animals subjected to UNDEX loading. Unfortunately, these experiments do not provide any insight into the UNDEXvulnerability of the marine mammal melon, which is a large fatty body (sited on the skull) that is presentin a subset of marine mammals (Odontoceti, or toothed whales). There is no terrestrial mammaliananalogue to the marine mammal melon, which is used for beam‐forming of various echolocating acousticpulses. Since the 1970s and for obvious ethical reasons, no intentional UNDEX testing has been carriedout on live animals. Some UNDEX testing has been carried out on marine mammal cadavers by D.R. Kettenet al., authorized through the required permitting process. Although the focus for these efforts wasprimarily on damage related to the marine mammal ear, hemorrhages were found in the acoustic jaw fatsand melons of some test subjects. This presentation will cover simulation of a subset of these experimentsproducing a range‐to‐effect result on the melon. Simulations are carried out using the U.S. Navy fluidstructureinteraction (FSI) code DYSMAS to simulate the UNDEX initiation and propagation through thefluid medium for a subset of these cadaver experiments. UNDEX pressure histories extracted at cadaverlocations are used as inputs to a finite element model of a simplified melon structure, where the materialand geometry are based on published information. For these preliminary simulations of the range‐toeffecttest series, shock spectrum results are examined to start investigating potential damagemechanisms and thresholds.
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