Accession Number : ADA218318


Title :   Sea-Water Magnetohydrodynamic Propulsion for Next-Generation Undersea Vehicles


Descriptive Note : Annual rept. 1 Feb 1989-31 Jan 1990


Corporate Author : PENNSYLVANIA STATE UNIV STATE COLLEGE APPLIED RESEARCH LAB


Personal Author(s) : Lin, T F ; Gilbert, J B ; Kossowsky, R


Full Text : http://www.dtic.mil/get-tr-doc/pdf?AD=ADA218318


Report Date : Feb 1990


Pagination or Media Count : 49


Abstract : Three tasks were performed in this report period. Their individual abstracts are summarized as follows: (I) Thruster Performance Modelings - The purpose of this work is to analyze underwater vehicle propulsion by applying Lorentz forces to the surrounding sea water. While this propulsion concept involves two different schemes, i.e. the external field method and the internal duct-type method, the current analysis focuses on the internal thruster scheme due to the space limitations and speed considerations. The theories of magnetohydrodynamic (MHD) pump jet propulsion are discussed. A so-called 'dual control volume' analysis to model the MHD thruster, and calculations of vehicle velocity and power efficiency are presented. (II) Sea Water Conductivity Enhancement - This work discusses the mechanisms of enhancing the electric conductivity of sea water. The direct impact of conductivity enhancement of sea water is the improvement of propulsion performances of marine vehicles that use the magnetohydrodynamic thrusts of sea water. The performance improvement can be in energy efficiency or in vehicle speed. Injection of strong electrolytes (acids or bases) into the main sea water flow in the MHD channel appeared to be the most logical way of achieving the purpose. (III) Status of Current Superconductivity Works - A survey of recent research in both low -T sub c and high -T sub c superconductivities is provided. It is generally true that high -T sub c superconductors carry critical current densities several orders of magnitude less than those of low -T sub c ones.


Descriptors :   *ELECTRIC PROPULSION , *ELECTROLYTES , *JET PROPULSION , *MAGNETOHYDRODYNAMICS , *SEA WATER , *UNDERWATER PROPULSION , ACIDS , CHANNELS , COMPUTATIONS , CURRENT DENSITY , DUAL MODE , EFFICIENCY , ELECTRICAL CONDUCTIVITY , ENERGY , EXTERNAL , IMPACT , INTERNAL , LIMITATIONS , LORENTZ FORCE , MARINE TRANSPORTATION , OPTIMIZATION , PERFORMANCE(ENGINEERING) , POWER , PUMPS , SPACE(ROOM) , SUPERCONDUCTORS , THEORY , THRUST , THRUSTERS , UNDERWATER VEHICLES , VELOCITY , WATER FLOW


Subject Categories : Submarine Engineering
      Electricity and Magnetism
      Electric and Ion Propulsion


Distribution Statement : APPROVED FOR PUBLIC RELEASE