SU811169A1 - Apparatus for exciting elastic oscillations in water - Google Patents

Description

A force (lifting), which serves to hold the explosion chamber in a position where its exhaust openings in the side wall are blocked and the cavity is sealed, and ensures that the initial pressure in the chamber is increased relative to the hydrostatic pressure, determined by the device design parameters. The decrease in exhaust backpressure of detonation products to the magnitude of only hydrostatic pressure. This is due to the depressurization of the annular gap by communicating it with the cavity of the explosion chamber through an opening in the nozzle. The initial position of the blasting chamber of the proposed design before it is immersed in water is supported by a fixing element with which the housing is provided, for example with a spring. The tightness of the internal cavity of the explosion chamber is provided by sealing rings located between the side surfaces of the housing and the chamber.

The drawing shows the proposed device.

The device includes a cylindrical body 1, an explosion chamber 2, a nozzle 3 of the explosion chamber, a device 4 for feeding and igniting the working mixture, an opening 5 for feeding the working mixture, an opening

0dl supplying the working mixture and transmitting a detonation impulse, annular gap 7, sealing rings 8, fixing element 9 defining the initial position of the explosion chamber in the housing, for example, a spring, exhaust holes 10 and opening 11 in the pipe to depressurize the annular clearance.

about a cylindrical body 1, open at the bottom end coaxially with it, an explosive chamber 2 placed in a movable manner, filled in the form of a container with a branch pipe 3. The working mixture is ignited in the device 4, where the working mixture is pumped through the hole 5, and the detonation impulse is transferred to the chamber 2 is carried out through the opening 6. The explosive chamber 2 is located in the housing

1c with the formation of an annular gap 7 sealed by sealing rings 8 from the external environment and until the explosive mixture explodes from the cavity of the explosion chamber 2. Before being submerged in water, the position of the explosion chamber 2 in the housing 1 is fixed by means of an element 9, for example a spring. An explosion of detonation products during an explosion is effected through exhaust openings 10 located in the side walls of the housing 1 and chamber 2, which are aligned at the exhaust. Before the explosion, the sealing rings 8 seal the internal cavity of the explosion chamber 2. To depressurize the annular gap 7 in order to prevent the creation of resistance, the movement of the chamber 2 during the explosion and the restriction of this resistance to the magnitude of only hydrostatic pressure is served by the opening 11 in the nozzle 3.

5 - The device operates as follows.

Filling the cavity of the blast chamber 2

: through holes 5 and 6 of the working gas

a mixture under pressure PO leads to the emergence of a force action on chamber 10, since it is movable relative to housing 1. The chamber 2 will be affected by forces determined by the pressure of the working gas mixture, the pressure RK in the annular gap and the hydrostatic pressure Ph in

15 water, with which the chamber 2 has contact on the outer bottom. The pressure of the gas mixture under the pressure of the RO, tends to move the movable chamber down from its extreme upper position, at which the exhaust openings of the housing 1 and the explosion chamber 2 are separated and the cavity of the chamber 2 is closed from the external environment. This force is equal to, where Si is the cross-sectional area of the inner bottom of the chamber. This power

5 displacing the chamber 2 downwards from the state of sealing its exhaust port, counteracts the forces caused by the hydrostatic pressure Ph at the immersion depth of chamber 2, equal to Рл-5н (Sn surface area of the outer bottom of the explosion chamber 2) and the lifting force caused by the pressure drop inside the explosion chamber 2 and in the sealed annular gap 7, is equal to () –3к, where RK is the pressure in the annular gap 7; SK - area of the annular gap 7.

In conditions of equilibrium of the blast chamber 2, the indicated forces will balance each other and the ratio

P, S,, + (P, P,). S ,. (one)

Taking into account that Si SK + Sz, expression (1) can be brought to the form

5p with p. with r. (9}

 ii -k (.)

Since Pi, .. Ph, then (3). From which it follows that the initial pressure in the explosion chamber is more hydrostatic in the ratio determined by the design parameters of the device by the ratio of the area of the bottom of the chamber 2 5z to the cross-sectional area Sz of the socket 3. When the gas mixture explodes, after the detonation impulse is transferred from the ignition chamber 4 to the chamber 2 through the opening 6, the chamber 2 will turn out of equilibrium and will move until the exhaust openings are aligned BEFORE the chamber 2

0 and housing 1. In order for the pressure differential in chamber 2 and annular gap 7 not to resist the movement of chamber 2, the annular gap 7 is depressurized through opening 11 in nozzle 3, which communicates it with the cavity of the explosion chamber. 2. The backpressure of the detonation exhaust produced by the displacement of chamber 2 to coincide with the exhaust ports 10 of chamber 2 and body 1 will be only hydrostatic pressure. After the hydrostatic pressure is exhausted, the explosion chamber 2 will return to its original position with the sealing exhaust hole 10, and the device is ready to repeat the cycle. During the entire operation of the device, the pressure in the RK in the gap 7 in the state of its sealing will remain less than the hydrostatic pressure Rk, Rn, which is necessary for the operation of the device, since part of the detonation products entering the gap 7 will condense after each cycle of operation. device, and the volume of this liquid phase will be insignificant compared with the volume of the gap 7.

The design of this device allows you to increase the initial pressure of the working mixture in the explosion chamber, without using special accessories, as it allows you to increase this pressure n compared to the hydrostatic in relation to the l - defined

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design parameters of the device. At the same time, the limits of increase in the initial pressure are expanded and, in addition, unproductive energy losses are reduced. Using this device produces a stable seismic signal with a good signal-to-interference ratio and a good resolution of the seismic record. In addition, it is possible to control the energy and frequency of the radiated signal.

Claims (2)

1. A device for initiating elastic vibrations in water, including an explosion chamber with an overlapping exhaust hole, characterized in that increase the efficiency and seismic efficiency of the device; the explosive chamber is made in the form of a movable container with a nozzle in the upper part and placed in a housing open at the bottom end, coaxially with him, with the formation of an annular gap between their upper ends, sealed by sealing gaskets, and the nozzle has a hole for depressurization of the annular gap, and the exhaust holes of the housing and the chamber are located in their side walls. 2. The device according to claim 1, characterized in that the case is provided with a lock of the initial position of the explosion chamber, for example, a spring, and to depressurize the cavity of the explosion chamber, sealing gaskets are provided between its side walls and the case. Information sources, taken into account in the examination 1.Balashkand M.I. and others. Sources of excitation of elastic waves during seismic exploration -on the water area x. M., “Nedra, 1977, p. 70-71. 2. Balaschkand MI, et al. Sources of elastic wave excitation during seismic exploration on water area x. M., “Nedra, 1977, p. 92-95 (prototype).