The development of magnetohydrodynamic thrusters
Magnetic fluid thruster (Magnetohydrodynamic Drive, MHD) is a channel through seawater built with a magnetic field, this magnetic field can generate electromagnetic force on the conductive seawater, so that it moves in the channel, if the movement direction points to the stern, the reaction force will push the ship forward. The first ship in the world that was officially put into use with a magnetic fluid thruster was the "Yamato 1", which was designed in 1992 and put into use in 1999. The first experiment reached a speed of 15 kilometers per hour. Technical Features
Compared with traditional mechanical transmission propellers (such as propellers, water pump water jet propellers, etc.), the difference between magnetic fluid propellers is that the former uses mechanical power as thrust and the latter uses electromagnetic force. Because of this, the magnetic fluid thruster does not need to be equipped with propeller blades, gear transmission mechanisms and shaft pumps, etc., and is a quiet thruster with no mechanical noise at all. Once modern submarines use this type of thruster, the vibration, noise and power limitations caused by mechanical rotation are fundamentally eliminated, and they can sail at extremely high speeds in almost absolute silence. According to theoretical calculations, its speed can reach 150 knots, which is impossible for any mechanical rotating propeller. Superconducting electromagnetic fluid propulsion is a new technology that directly converts electrical energy into fluid kinetic energy and replaces traditional propeller propulsion with jet propulsion. It has the characteristics of low noise and safety, and has great value in special ship propulsion applications. The Chinese Academy of Sciences started the research on superconducting magnetic fluid propulsion technology in 1996, and successfully developed the world's first superconducting spiral electromagnetic fluid propulsion experimental ship Future Trends
One of the disadvantages is that at the current technical level, magnetic fluid propulsion technology is expensive and slow. The second disadvantage is that this technology requires a large generator, which increases the weight of the boat or submarine, and the power system that drives the generator, such as direct drive traditional thrusters, is faster than MHD technology. A feasible improvement plan is to install an MHD drive on a traditional submarine and use battery power. Guarantee the temporary "stealth" of the submarine in the combat state.