An Evaluation of Direct Current Electromagnetic Propulsion in Seawater
Abstract
Electromagnetic seawater thrusters may be classified in one of three general categories: internal duct dc, external field dc, and peristalic ac. Internal duct dc thruster offers the advantages of low magnetic field leakage, simple construction, and potentially high reliability. The most efficient internal duct configuration consists of a converging inlet nozzle and a straight discharge duct. Ideal efficiency calculations based on the one-dimensional Bernoulli equation show that thrusters should be designed with large cross- sectional areas and operate at low discharge velocities. In practice, this may be accomplished by using multiple thruster ducts. Conductivity enhancement, high magnetic fields, and long electrodes also improve efficiency. While the magnetic field-volume requirements for thruster capable of propelling full-size (2000 ton displacement) submarines appears beyond the present technology, it may be feasible to use superconducting magnets to build high efficiency, internal duct thruster capable of maneuvering small (approx. 10 ton displacement) submersibles.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1979
- Accession Number
- ADA074830
Entities
People
- George T. Hummert