Since the first submarine was built, designers have continually endeavored to increase the cruising speed and the depth of dive, and to reduce the level of noise of the power plants . . . . The problem, of course, is a considerable one. Experts of a number of countries consider its solution to lie in development of power plants which are new in principle. Particular attention is directed to electromagnetic ram jet engines, which operate on the principle of creation of a jet stream generated by electroma$netic forces.
Such a power plant is interesting in that, as noted by foreign experts, it has substantial advantages. It is significantly more powerful, which in turn permits higher speeds and greater displacement for submarines. The level of vibration is reduced; there is a substantial decrease in the noise of operation of the power plant because of the absence of the traditional bladed propeller; and there is a reduction in the number of moving parts of the mechanical and electrical systems.
But the main advantage is that in the new power plant there are combined to a certain degree a motor (a machine which converts some type of energy into mechanical work, for example a rotating shaft) and a propelling agent (a device for converting the energy of the motor into work expended in overcoming the resistance to motion of the submarine. )
The idea, as may be seen, is intriguing. But how realistic is it?
In 1962, accounts were published in the foreign press of an electromagnetic engine designed by American expert Wayne H. Philips; adaptable to a submarine 200 meters in length and capable of variable speeds.
In 1964 P.A. Dorakh published the accounts of research in which he asserted that knowledge in the field of magnetism and phenomena of superconductivity makes it possible to improve the tactical-technical capabilities of electromagnetic engines to the extent that they can be used as a propelling agent for submarines. Dorakh illustrated his demonstration with a diagram of an electromagnetic motor developed by Engineer S. Bey.
Later the first practical strides were made in this direction. In 1966 the mechanical engineering department of the University of California built and tested a model submarine (3.05 meters in length, 0.45 meters in diameter, and weighing 408 kg) with an EHS-1 electromagnetic motor. As an electrical source a lead-acid storage battery is used (with a weight of 150 kg). In tests the model achieved speeds of more than 1 knot.
It should be noted, however, that the idea of a ram jet engine is not all that new. As early as 1661 the English inventors Tolgood and Hayes patented a vessel design in which the “pusher” was a pump device. It was the forerunner of modern water drive engines. In 1738 the Russian academician Daniel Bernoulli wrote his work “Hydrodynamics,” in which he expounded the theoretical basis of reaction of a jet of water for propelling a vessel. Utilization of hydrojet engines for submarines was first proposed in Russia in 1880 by long range navigator Captain I. S. Lostevich and a mechanic of the Izhorskiy Plant, F. Ye. Korichia.
There are several projects underway abroad to develop electromagnetic ram jet engines for submarines.
One of the more simple planned designs is a model with a bi-polar system of direct current with an external pole. In it a magnetic pole is created by the coils of an electromagnet. The threads of the coil are placed inside the hull of the submarine in a horizontal position. On them, along the right and left sides, are placed conducting electrodes, which are in direct contact with sea water. As a result, on each of the elementary volumes of water surrounding the boat there are resultant magnetic forces and electrical fields (Lorenz fields). They seek to drive the water to the rear along the longitudinal axis of the boat’s hull, which forces it to move forward. But the efficiency of the work of such an engine depends on the magnetic field and the electric conductivity of the sea water, which is many times less than that of metallic conductors.
This deficiency, it is noted by foreign experts, is not present in the induction electromagnetic ram jet propelling device of the initial type. In the latter, an electric current is induced not in sea water, but rather in an intermediate highly conductive liquid (a liquid metal). Here great force is generated, which is used in creating a jet of sea water. The role of converter is played by a flexible membrane. Such a propelling device could be called an electromagnetic water jet. However, its design technically complex because of the necessity to transmit great force from a layer of liquid metal to the sea water by means of the flexible membrane.
An attempt was made to avoid these shortcomings in the electromagnetic ram jet propeller in a project conducted by H. Albert and E. Zhako (of Michigan University). The authors created a self-propelled model of a noiseless submarine, without bladed propellers or a rudder.
The model is set in motion by forces generated as a result of fluctuations in the external casing of the hull. In other words, the biotechnical principle is used to create motive power. A similar method of movement through water is used by some marine animals, particularly by skates. Their motive power is generated by pulsations and a unique displacement of wave profiles along their elastic fins.
As applied to submarines, this principle of motion is called a “skin motor.” It consists of the fact that movement and control of the model are accomplished by means of a special external flexible casing, which creates fluctuations in the form of progressive waves, which run along the hull on the side of the stern extremity of the model. The fluctuations are generated by means of a series of electromagnetic rings placed along the flexible casing of the hull on its internal side.
Upon a change of direction of the electric current around the electromagnetic rings, the external casing is subjected to the influence at first of radial forces from their center, and then to opposite pulling forces. This process is so distributed in time that it creates a progressive running wave, which insures the necessary stresses for movement of the boat.
A propellant device of this type can serve simultaneously as a means of control; that is, to change the course of the submarine vessel and to accomplish dives and surfacing.
In the opinion of foreign specialists, the application of electromagnetic ram jet propellant systems of various types of submarines and on large-tonnage submarine transport vessels will result in overcoming a number of technical problems, which according to them are deterring further developments and improvements in the tactical-technical characteristics of submarine vessels.[ This article by CAPT-Lt (Res) A. Popov, SUBMARINES and·····SEA SKATES was published in KRASNAYA ZVEZDA in Russian, 11 August, 1974.]