Prediction of the Pressure Signature of a Ship in a Seastate
Abstract
Presently, all US ship mine vulnerability studies are based on the restrictive assumption that the ship is traveling through a calm sea. Our goal is to remove this restriction and thereby allow a more accurate assessment of ship vulnerability to sea mines. We are developing a model to predict the pressure field surrounding a ship advancing in a seaway. This pressure field consists of a steady component due to the forward motion of the ship and an unsteady component due to the oscillatory motions induced by the incoming waves. We are particularly interested in predicting the pressure signature on the seafloor, because this is where pressure-sensing mines are typically located. Since the ship pressure field decays with depth, high-frequency components of that field are filtered to a greater extent as depth increases. Additionally, the mine samples the ambient pressure field at varying but relatively low frequency. Both of these observations suggest the need for a model that includes a seafloor and is accurate at low frequencies. Most conventional strip theories assume the fluid to be infinitely deep and are valid only for high frequencies. They are not appropriate for our purpose, which is why we have chosen a three-dimensional formulation.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 30, 1998
- Accession Number
- ADA569982
Entities
People
- Kennard Watson
- Mark Hyman
- Thai Nguyen