Ultrafast detection and imaging of underwater blasts
Abstract
Imaging through particle- and bubble-laden ocean water remains a challenging problem for testing and evaluation of energetic systems due to the nature of underwater explosive tests. The test environments typically consist of meter-scale bodies of water which contain suspensions of particulate media and bubbles—both leading to significant scattering and attenuation of propagating light. Characterization of the explosive breakout and vapor-liquid interface during the initial explosion further requires measurements with limited access (i.e. single-side detection) and sufficient temporal resolution. The objectives of this proposed effort are to develop time-gated imaging approaches for underwater applications using gating techniques with high-brightness, ultrafast laser sources. These include (1) ballistic imaging approaches for imaging wave propagation, and (2) time-gated backscattered light for ranging and velocimetry of vapor-liquid interfaces. Optical-gating approaches have been applied in a number of multiphase flow applications, but the limitation and potential in more dispersive media (water) have not been addressed to date. This effort will address the scattering, depolarization, attenuation, and nonlinear dispersion of the ultrafast light in underwater environments. Lab-scale efforts to characterize ballistic imaging and ballistic backscattered light performance for blast-wave imaging will open new opportunities for optimizing and scaling these techniques for full-scale field testing.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Mar 31, 2025
- Source ID
- N001742010022
Entities
People
- James B Michael
Organizations
- Iowa State University
- United States Navy