Electromagnetic Fluid Surface Propulsion Mechanism

The magnetohydrodynamic (MHD) propulsion by surface is a neoteric propulsion technique. The Lorenz force is induced around the navigation and propel the near-wall seawater, thus the navigation may be propelled by this way. It not only replaces the conventional propeller machines such as propeller or jet propulsion, eliminating the vibration and noise caused by the rotating drivers, but also avoids propeller cavitations. The most striking feature is quiet and high efficiency. Great achievements have been made by the United States, Japan, the former Soviet Union and others countries since the MHD propulsion was proposed in the 1960s. However, there are many problems need investigated to realize the practical using.By utilizing numerical simulation methods, the mechanism of MHD propulsion by surface has been investigated. Being of the advantages of saving space, enlarging the driving surfaces and drag reduction, the surfaces of navigation were used as the propulsion drivers. As the striking features mentioned above, the MHD propulsion by surface will may become the best drive way in the 21st century.Based on the basic equations of electromagnetic field and hydrodynamics governing, composing with proper boundary conditions, the basic mathematical models were structured. The basic concept of Finite Volume means was introduced. The flow flied and velocity distributions around the propulsion model were simulated by Finite Volume means. The effects of propulsion for different strength of Lorenz force, angle of attacks, scope of actions and width of electro-magnetic poles were studied, and finally, the optimal proposal style of MHD propulsion by surface was proposed.The investigation results revealed that the effects of magnetohydrodynamic propulsion by surface have closed relationship to the action coefficients. Propulsion effects may improve significantly with the increasing of action coefficients. With the increasing of the angle of navigation attack the effects drop slightly. By discussing the electro-magnetic poles embedded scope of navigation demonstrated that the middle embedded condition may obtain larger momentum of navigation, while the back embedded condition may get of better drag reduction effects. The electric field, magnetic field and electromagnetic force have better penetrated ability but less near-wall strength whiles the propulsion units of wider magnetic poles. The deeper penetrate depth of the propulsion unit the more significant change for the fluid flow fileds.