Marine Mammal Lung Dynamics when Exposed to Underwater Explosion Impulse

Area of Science:

• Marine Biology
• Biophysics
• Computational Fluid Dynamics

Background:

• Limited knowledge exists regarding marine mammal susceptibility to primary blast injury (PBI).
• Traditional PBI analysis relies on outdated methods using terrestrial mammals as surrogates.
• Advances in computational power and modeling tools necessitate updated approaches for marine mammal safety.

Purpose of the Study:

• To develop and apply advanced computational models for assessing marine mammal PBI from underwater explosions (UNDEX).
• To improve the accuracy of safe range and injury zone calculations for marine mammals exposed to UNDEX.
• To leverage morphologically accurate marine mammal models and material properties for more realistic simulations.

Main Methods:

• Utilized Dynamic System Mechanics Advanced Simulation (DYSMAS) fluid-structure interaction (FSI) software.
• Simulated UNDEX phenomena, including shock wave and bubble pulse propagation.
• Integrated fluid and structural analyses with marine mammal morphometrics and tissue material properties.

Main Results:

• DYSMAS simulations of gas bubbles in water closely matched classical bubble dynamics models.
• Simulations of bubbles within tissue and rib structures showed radial oscillation and significant local material strain.
• The models demonstrated the transmission of UNDEX energy to cetaceans, focusing on thoracic cavity and lung response.

Conclusions:

• Advanced computational modeling offers a scientifically defensible method to understand UNDEX effects on marine mammals.
• DYSMAS provides a powerful tool for creating accurate injury zones and safe ranges, replacing outdated surrogate methods.
• This research enhances the understanding of PBI in marine mammals, crucial for conservation and mitigation efforts.