SU748923A1 - Electric-arc gas heater - Google Patents

Description

The invention relates to electrical engineering, in particular to electric arc high-temperature gas heaters, and can be used in various high-temperature technological processes (electrothermal, plasma-chemical, plasma metallurgy, etc.). Electric arc gas heaters are known, which contain electrodes, an interelectrode insert and devices for supplying heated gas D), (2). In these electric arc gas converters, the arc burns between the electrodes and is stabilized by a gas vortex. The heated arc gas is removed either through one tubular electrode, or through two. Also known is an electric arc gas heater containing two parallel-installed hollow cylindrical electrodes, an interelectrode insert in the vnde of a bent pipe, isolated from the electrodes by gas supply rings, and an arc rotating unit (3). The purpose of the invention is to increase the power of the heater due to the intensification of heat exchange between the arc and gas. This goal is achieved by the fact that, in the proposed device, the interelectrode insert is provided with two additional straight-line pipe segments, one ends of which are attached to the electrodes through the said insulating rings, and others through additional similar rings to the bent part of the insert. The rotation of the arc is carried out by a solenoid encompassing both electrodes. FIG. I schematically depicts an electric arc gas heater; a slit; in fig. 2 - diagram of the action of forces on the arc in parallel inserts. An arc arc gas heater consists of two parallel-installed hollow cylindrical electrodes 1, covered by a common solenoid 2. The interelectrode insert is made of a bent part 3 and two straight line pipe sections 4. Devices 5-7 serve for tangential gas supply in curvilinear sections 3 and straight lines 4 interelectrode inserts and electrodes 1. All devices 5-7 for gas supply are made of electrically insulating materials. Straight line

the lengths of the pipes 4 are arranged parallel to each other with the center distance, which is preferably 2.01-3.0 of the largest radial size. Their walls are made of ferromagnetic material. They are isolated both from curvilinear inserts, and from electrodes. The straight line sections of the pipes 4 can be both integral and consisting of separate sections that are isolated from one another. In this case, the tangential gas supply devices 7 can be located both between the insertion areas and between the sections.

The arc heater works as follows.

After supplying the working gas, coolant, power supply to the electrodes and the solenoid, an electric arc is initiated between the electrodes at low arc currents in order to reduce the effect of parallel arcs on one another. The arcs, stabilized by a gas vortex, are located in the paraxial zone of the interelectrode insert. A subsequent increase in the arc current to the nominal value leads to an increase in the interaction of the arcs in parallel parts of the insert. The arc posts, pushing away from each other, are displaced from the vortex axis.

The arcs in both straight lines of the insert, placed in a stable equilibrium position at some distance from the axes of their inserts, are blown by the gas flow, which intensifies the heat exchange between the arc and the gas, i.e., increases the voltage gradient along the length of the arc and, accordingly, the power electric arc heater with the same, in comparison with the known devices (3), gas consumption, current value, arc length and efficiency ..

Increasing the voltage gradient along the arc length without increasing the arc current favorably affects the current-voltage characteristic of the heater (its ascending branch is steeper than that of the known heaters), which allows it to operate in a beamless mode at lower arc currents.

The isobregeiii allows to increase the power of the electric arc gas heater by 1.5–2 times at the same flow rate, gas, current strength, arc length and efficiency with the same known device | 3).

Claims (3)

Invention Formula . An arc-type gas heater containing two parallel-installed hollow cylindrical electrodes, an inter-electrode insert in the form of a bent pipe, isolated from the electrodes by rings with channels for supplying gas to the discharge chamber, and a solenoid, characterized in that, to increase the power of the heater, the insert is equipped with two additional straight pipe segments, one ends of which are docked to the electrodes through the mentioned rings, and others through additional similar rings to the bent portion of the insert. 2. Electric arc gas heater, characterized in that the solenoid covers both electrodes. Information sources), taken into account in the examination 1. Koroteev, AS and others. Generators of low-temperature plasma. M., “Science, 1969, p. 20. 2. Koroteev A. S., et al. Low-temperature plasma generators. M., “Science, 1969, p. 21. 3. USSR author's certificate number 524336, cl. H 05 B 7/18. 1976.