RU2071163C1 - Method of and magnetohydrodynamic generator for producing electrical energy - Google Patents

Abstract

FIELD: power engineering; magnetohydrodynamic generators. SUBSTANCE: closed toroidal channel is connected to several combustion chambers and filled with hydrogen. Oxidizer is sprayed into combustion chamber and products of oxidation reaction in the form of shock waves arrive at toroidal channel. Oxidizer feed rate and sequence are chosen so that shock waves form alternating high- and low-pressure regions moving along channel. Volume charge is produced in channel by means of thermionic cathode 4; this charge induces electric current in output winding of magnetic circuit 15 due to electromagnetic interaction with magnetic circuit 5 embracing the channel and carrying field windings 14. Inner surface of body of channel 2 is coated with insulating material 3 that divides channel into isolated sections. Channel sections are series-connected to thermionic cathodes and field windings forming several electric circuits. EFFECT: improved design, facilitated procedure. 2 cl, 5 dwg

Description

 The invention relates to energy, and in particular to the problems of generating electricity using MHD generators.

 Known methods for the production of electricity and magnetohydrodynamic devices for their implementation (application VNR N T / 34290, US Pat. N 4339678, auth. St. USSR N 782693). These methods are based on obtaining a working fluid in the form of an electrolyte or plasma, with the help of which electrical energy is obtained as a result of electromagnetic induction. The devices for implementing the known methods mainly comprise a channel through which the working fluid moves, an electromagnetic system for creating an electromagnetic field and electrodes for removing electricity. However, these methods and devices involve a significant consumption of components to obtain a working fluid, which leads to a decrease in the efficiency of the device.

 Closest in their technical solution to the proposed method and device is a method of converting the energy of a substance flow into electrical energy according to US Pat. GDR N 269730 and a device for producing electrical energy according to US Pat. USSR N 753372.

 In accordance with this method, a combustible gas that is burned in oxygen is preheated. As a result of burning, plasma is obtained and made to pulsate with a certain frequency. Then, the pulsating plasma is synchronously with current fluctuations in the electric circuit supplied to the electrodes and, as a result of deionization, the plasma energy is converted into electric energy.

 A device for generating electric energy comprises a channel in the form of a sealed torus, in which a working fluid is located, consisting of ferromagnetic spheroids, a pipe for supplying and discharging air, a heater and a magnetic system with a winding.

 The considered method does not allow to obtain a significant increase in efficiency, since it involves a significant consumption of components for plasma production. The prototype device is quite complex due to the high requirements for the accuracy of manufacturing the channel and the spheroids located in it. In addition, it is not reliable enough, since it requires additional mechanical means to ensure the unambiguous movement of spheroids.

 The objective of the invention is to increase the reliability of operation and obtain a higher coefficient of performance.

 This is achieved by the fact that in a closed channel containing a vapor-gas mixture, a hydrogen oxidation reaction is organized. In this case, pulse oxidizer is injected into the closed channel. As a result, a gas flow is created, moving in the form of a shock wave. During the movement of the flow, the sign of its space charge existing in the low-pressure regions of the shock wave is changed, and the interaction of the space charge with the field windings located on the magnetic circuit is organized, and the AC voltage is removed from the output channel winding.

 Moreover, a device containing a closed toroidal channel and an electromagnetic system with windings is additionally equipped with combustion chambers connected to the channel. Combustion chambers through nozzles of electromagnetic pumps are connected with the atmosphere. Inside the housing, a dielectric coating is made. The channel has thermal cathodes. In this case, the non-magnetic case and the thermal cathode are separated by a dielectric coating into electrically insulated sections, with each section of the housing being electrically connected in series with the corresponding thermal cathode and the excitation winding with the formation of an electric resonance circuit.

 The speed of the shock wave is kept constant using an automation system that controls the amount of air entering through the electromagnetic pumps. When an electrical load is connected, space charges begin to slow down the shock wave, then the automation system begins to supply a larger amount of oxidizer, opening the damper, and the wave speed again reaches its nominal value. The speed of the shock wave is chosen so that the systems interacting with the wave (combustion chambers, electromagnetic pumps) are in an optimum resonant mode of operation in terms of power.

 The proposed set of operations, elements and relationships allows us to achieve the goal of the invention by optimizing the process of converting the energy of a moving stream of matter into electrical energy, as well as the technical implementation of the sequence of events and requirements due to physical laws.

 In the study of known technical solutions in the art, the totality of the features that distinguish the claimed invention was not identified. This solution is significantly different from the known ones.

 Since the claimed technical solution differs from the known ones, it obviously does not follow from the prior art and, accordingly, has an inventive step.

 Since the claimed solution can be implemented by modern means and materials, it is industrially applicable.

 In FIG. 1 shows the main components of the MHD generator; figure 2 an example of connecting combustion chambers to the channel; figure 3 the design of the electromagnetic pump; in FIG. 4 timing diagrams of the electromagnetic pump; figure 5 electrical diagram of the MHD generator.

 Figure 1-5 indicates: 1 channel, 2 case, 3 dielectric coating, 4 thermoelectrode, 5 magnetic circuit, 6 combustion chamber, 7 - high pressure region, 8 low pressure region, 9 magnetization reversal windings, 10 piston, 11 air intake, 12 nozzle, 13 - shutter, 14 field winding, 15 output winding.

 The essence of the method of producing electrical energy is as follows.

 The closed channel is filled with hydrogen and a gas-vapor mixture. An oxidizing agent is injected into the channel at certain places and at certain points in time. Under the influence of high pressure and temperature, the oxidizing agent reacts, as a result of which a shock wave is excited in the channel. This wave has two areas of high pressure and two low. The wave velocity is maintained above the speed of sound for stability of the fronts of pressure regions.

 The shock wave excited in the channel is maintained in resonance due to the organization of the oxidizer injection system. The resonance in a traveling wave for a closed loop is determined by an integer number of wavelengths laid along the midline of the channel circumference. To create a symmetric wave, the minimum value of this ratio is 2. In low-pressure regions under the influence of shock and thermal ionization, the mixture of gases and steam is in the ionized state. In the areas of high pressure of a traveling wave, ions and electrons recombine, and these areas are electrically neutral and do not conduct electric current.

 Areas of ionized gas are space charges. To obtain electric energy, it is required to change the sign of the space charge in the process of moving it along the channel. This purpose is served by a thermal cathode introduced into the channel along its entire length, and excitation windings connected with a gas coil by a single magnetic circuit. The thermal cathode interacts with the space charge at any point in the channel in which it is located. As a result of a change in the sign of the space charge, an EMF is induced in the field windings. If the thermal cathode has a negative potential relative to the housing, then conduction electrons will tend to leave the thermal cathode in the space charge region and increase the negative potential of this region even more, and since the space charge region moves, the magnetic flux is more and more amplified and the negative potential of the thermal cathode increases. The thermal cathode + space charge system is one of the plates of a kind of capacitor. Another lining of this capacitor is a channel body having a dielectric coating. The capacitance of this capacitor and the inductance of the field winding determine the natural frequency of the electric oscillatory circuit with which the potential at the thermal cathode changes. With a positive potential on it in the space charge region there will be a lack of conduction electrons in comparison with ions. With a negative excess.

 To prevent oxidation of the thermal cathode, an excess of a reducing reagent (hydrogen) is maintained in the channel. Upon completion of work, i.e. when the output winding closes to an electric load, the space-charge region will slow down more strongly and penetrate deeper into the high-pressure region, where free carriers will seem to freeze into the dense front of this region, moving with it. At the same time, the amount of oxidizing agent entering the channel is increased so that the wave velocity remains nominal.

 The high-pressure region of the shock wave isolates the space-charge regions from each other and prevents the formation of a short-circuited loop through the gas, and is also a piston that advances the space-charge along the channel.

 MHD generator contains (Fig. 1) a channel 1 formed by a toroidal casing 2 of non-magnetic metal. A dielectric coating 3 is made inside the housing 2, thermal cathodes 3 are located here. A magnetic circuit 5 is located around the housing. The housing 2 has (Fig. 2) several quarter-wave branches, which are combustion chambers 6. In this example, there are eight such branches. The minimum number of branches for a symmetrically traveling wave is six. The total volume of the combustion chambers 6 is chosen equal to the volume of the channel or slightly larger. The cross-sectional area of the communication channel with the combustion chamber is selected 2-3 times smaller than the cross-sectional area of the main channel. When the mixture is burned in chambers 6 in the channel, regions of high 7 and low 8 pressure are formed. The oxidizer is injected into the combustion chamber by a high-speed electromagnetic pump (Fig. 3). The main node of the pump is an electromagnet with windings 9 and a movable core 10. Magnetization reversal of the core allows to reduce the mass of the moving part. The operation of the pump is performed in accordance with the timing diagrams shown in FIG. The movable core is a piston, at the end of which a titanium movable valve is worn. When the average pressure and pressure between the piston and the movable valve of the compressible gas are reached, the valve moves a small distance, opening the way for the oxidizer through the air intake 11 to the nozzle 12. Through the nozzle, the gas enters the combustion chamber 6. The shock wave velocity is maintained constant by means of the damper 13, which regulates the flow of oxidizer.

 The field windings 14 are located on the magnetic circuit 5, on which the output winding 15 is located.

 To prevent the formation of short-circuited turns along the metal parts of the structure of the housing 2, it is divided into four independent electrical resonant circuits isolated from each other by dielectric coatings 3. Each circuit has its own thermal cathode 4, the field winding 14, and a part of the housing 2 connected to them.

 The MHD generator operates as follows.

 An oxidizer is injected into the channel 1 and the combustion chambers 6, filled with a gas-vapor mixture and hydrogen. The injection into the chambers 6 is synchronized in such a way that high-pressure and low-pressure regions of one direction of rotation are created. The moving regions of the ionized vapor-gas mixture are space charges, which change their sign with the help of thermal cathodes 4. As a result of the interaction of space charges that change their sign, EMF is induced in the excitation windings 14, and the AC voltage is removed from the output winding 15.

According to the claimed proposal, calculations and design of individual nodes of the MHD generator have been performed. The channel is designed for a maximum pressure of 160 bar at the highest temperature of 300 ^o C. The design of the MHD generator is economical. A sufficiently low hydrogen consumption allows it to be used to create engines for cars and vehicles, as well as for other technical purposes related to the economical and environmentally friendly generation of electricity.

Claims (2)

 1. A method of producing electrical energy through the interaction of electrodes and plasma oxidation produced by the oxidation reaction, characterized in that the pulse oxidizer is injected into a closed channel, creating a gas stream moving in the form of a shock wave, during the movement they change the sign of the space charge in the gas stream and organize the interaction of space charges with excitation windings, which are located on the magnetic circuit, and remove the AC voltage from the output winding of the channel.  2. MHD generator containing a sealed closed toroidal channel with a housing made of non-magnetic material and an electromagnetic system with windings, characterized in that the channel is connected to combustion chambers that are connected to the atmosphere through the nozzles of the electromagnetic pumps, a dielectric coating is made inside the housing, and the channel is located thermal cathodes, the casing is divided by a dielectric coating into electrically insulated sections, and each section of the casing is electrically connected in series with the corresponding thermal cathode and bmotkoy electrical excitation to form a resonant circuit.

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