The analysis of effects and theories for electromagnetic hydrodynamics propulsion by surface
电磁流体表面推进机理与效果分析

The electromagnetic hydrodynamics(EMHD) propulsion by surface is performed through the reaction of electromagnetic body force, which is induced in conductive flow fluid (such as seawater, plasma and so on) around the propulsion unit. Based on the basic governing equations of electromagnetic field and hydrodynamics, by numerical simulations obtained by the finite volume method, the characteristics of flow field structures near the navigating and the strength variation of propulsion force are investigated at varying positions (the angle of attack). The results show that surface electromagnetic body force can modify the structure and the input energy of flow boundary layer, which enables the navigation to obtain the thrust. With the increase of interaction parameter the effect of viscous resistance and pressure drag to navigating decrease and the nonlinear relationship between propulsion coefficient and interaction parameter tends to be linear gradually. The strength of propulsion force depends mainly on the electromagnetic body force. The lift force can be improved effectively through the EMHD propulsion by surface at an angle of attack for navigating. The navigating surface can be designed as working space of propulsion units, which is of certain significance for optimizing the whole struction and improving the efficiency.