Fundamental Study On Alternating Magnetic Field MHD Thruster

As a new type of ship propulsion, AC Magnetohydrodynamic(MHD) propulsion apply alternating magnetic field through seawater, then a Lorentz force will act to move the seawater and thus drive the ship to move. The system eliminates the conventional rotating driving components, the absence of mechanical propeller system will lead to a reduction in the mechanical noise generated and make the arrangement of ship more expedient. Compared with DC-MHD propulsion, AC mode has no electrode and doesn't apply electric field to fluid directly. Thus it avoids the detriment and noise caused by the air bubble generated by electrolysis, and makes the ship more quietly. These characters will help to develop a more efficient ship thruster.In order to provide the theoretical and experimental guides for the design and fabrication scheme of the engineering prototype of AC-MHD propulsion in the future, this thesis is focused on the following researches related to the AC-MHD propulsion.A general review on the development and current situation of the AC-MHD propulsion is presented.With the theory of electromagnetic field and the theory of hydrodynamic, a 2-D mathematics model of internal planar AC-MHD thruster is built. On the basis of mathematics model, the coupled field of alternating magnetic field and fluid field in the channel of a 2-D AC-MHD thruster is simulated using finite element method.To verify the result of the experiment by Yoshiro Saji in 1990's, the author try to calculate the simplified 2-D coupled field of the tester, and get a satisfied result.