"The underwater explosion", "underwater storm" - the so-called figurative powerful high-voltage electric discharge in liquid, first obtained an engineer LA Yutkin. He himself called his discovery " electro hydraulic effect ".
The electric spark slips between electrodes immersed in the liquid under certain conditions, produces an unexpected effect. If there will be a spark solid, it will be crushed powder, no matter how hard it may be, and above the spark gap column of liquid is thrown up high. What is obtained by electrical discharge?
The location of the discharge pressure immediately formed in tens and hundreds of thousands. Atm. (See. Diagram). The microscopic channel over which the spark jumps, has an extremely large energy density, instantaneous power reaches enormous quantities. For example, a plant with a capacity of only 0.5 kW, you can get instant output of 100 000 kW and more.
The water surrounding the spark, with great rapidity fly away, creating a first hydraulic shock. A void - a cavity, which immediately filled with water; obtained another powerful hydraulic shock - cavitation. Electrical energy is thus without any intermediaries converted into mechanical. Opening Yutkina be possible to use in practical applications. In his Leningrad laboratory were born one after the other instruments and tools, which joins the common name for the word "electro-hydraulic" - electro-hydraulic cutter, electro-bit, electro hydraulic nozzle and others. The chisel hammer, cutter cuts, unit injector supplies fuel into the cylinder of a diesel engine and spray it, it has performed the same work as that of conventional tools and instruments, but the word "electro-hydraulic" makes them quite unlike the "ancestors." As no one has the bit in no piston pump, which would be pumped liquid drill, not spinning, gnawing their cutting edges in solid rock.
Fig.1 The shape and arrangement of the pressure around the spark discharge (for L.A Yutkin): A - area of the spark discharge. B - Zone of destruction. It almost all materials break down into tiny particles, and the liquid acquires the properties of brittle solid. C - hardening zone. Here, many of the materials are destroyed and metals naklepyvayutsya (seal surface). F - in this zone there is a strong push out action. D - compression zone. Here there is the movement of large volumes of fluid.
Here is how one of the new tools - electro-hydraulic drill (see. Figure 2). In the center of the sleeve is placed a steel rod - electrode. A second electrode is a metal tube - the crown. When the current is turned between the bent tip of the center electrode and the nearest tooth crowns arise electrical discharges. In operation, the drill bit remains stationary while the central electrode is rotated at a low speed, so a spark, running with a tooth on tooth traverses the entire circumference of the crown. In another, more recent designs rotating electrode replaced fixed, but instead bent away tip is installed a plate-plate. Spark, running radially plates also bypasses the entire circumference of the crown. Electro hydraulic shocks , arising at each discharge, hollow material, which put the drill, gnawing round hole with a diameter slightly larger than the diameter of the crown. The crushed rock is washed with water, which is pumped through the tube into the drill. So you can drill a hole in the hardest rocks. Bur at the same time as other electro-tools, not blunts and does not wear out. Consumption of electricity for all the work is very small. For example, powerful electro-hydraulic crusher during the processing of gravel on sand consumes only about 7 kilowatt-hours of energy per ton of rubble.
Fig. 2
With electrohydraulic effect can split the huge stones compacted concrete during installation, the pile hammer, abrade into fine powder metals. His first experiments LA Yutkin began to conduct as a student with a small school influence machine 3W, which gave power to 30 thousand. Volts. If you have a school has such a machine, it will not be difficult if you want to build a small plant and demonstrate the effect of electro-physics lessons. In a small tub on insulating supports necessary to strengthen the electrodes from scraps of wire with a diameter of about 0.5 mm (Isle of each other). The distance between them - the main spark gap - almost steals (50-80 mm). The positive electrode must be insulated along the whole length, except its front end. The wire can take plastikatovoy CONTACT-in insulation. Connect the wires to the electrodes from the poles influence machine. Between plus and minus machine includes a capacitor - a common Leyden jar. The electrical circuit other than the main spark gap must be two so-called forming spark gap. For this purpose, each of the wires from influence machine, it is necessary to cut and attach to the nickel beads with a diameter of 15-20 mm. The distance between the balls and nearly steals. With such a device, of course, do not get underwater explosion capacity of 100 th. KW and a water fountain, raised a small spark of a calm surface, it looks impressive, too.