RU2477839C1 - Pulsating flow generator - Google Patents

Abstract

FIELD: physics.

SUBSTANCE: generator has a hollow rotor with output windows, which is connected to the shaft of a first motor and is controlled by a controlled unit, a cylindrical stator with an inlet pipe and two output windows lying diametrically opposite on its surface and connected to outlet pipes which are connected to each other by an additional pipe in which there is a flow section regulator which is configured to alternately close said pipes. The flow section regulator is in form of a piston capable of back-and-forth and rotational movement while closing the pipes in antiphase.

EFFECT: broader capabilities of controlling flow pulsation with different laws.

3 cl, 2 dwg

Description

The invention relates to variable flow generators designed to generate pulsed pressure and / or working medium flow in the study of metrological characteristics of pressure and fluid flow meters, and may find application in the instrument industry with metrological certification of these measuring instruments.

A known variable flow generator, which uses the change in the area of a rectangular slot located along the generatrix of the cylindrical stator (Flow pulsator PR-1. Technical description P1-00-00 TO, 1973) - [1]. The controlled medium is fed into the internal cavity of the stator through the inlet pipe. The change in the size of the area of the slot occurs when the rotor rotates in the form of a cylinder truncated by a plane at an angle to its longitudinal axis. In this case, the flow rate through the aforementioned slot with uniform rotation of the rotor changes according to a sinusoidal law. The stream passing through the slot of variable area enters the test section in the form of a pipeline with the test flowmeter installed in it and then into the drain tank through the drain pipe. The frequency of flow pulsations is determined by the rotor speed. By changing the speed of rotation of the rotor and recording the testimony of the test flowmeter, you can determine the frequency response of the test flowmeter. This well-known generator is characterized by the difficulty of obtaining flow pulsations of the required amplitude and shape in a wide frequency range, since for this it is necessary to control the movement of a large mass of liquid, and this requires the creation of significant pressure of a controlled medium, which in some cases is practically not feasible. In addition, in generators of this design, significant pressure drops occur, which introduces additional errors in the test results, not to mention the presence of large pipeline vibrations, especially at low frequencies.

A device is known "Hydromechanical pulsator" according to the copyright certificate SU No. 1013764 A, G01F 25/00, published on 04.23.83. Bull. No. 15 - [2], containing a cylindrical body with input and two output windows of a rectangular shape located in mutually perpendicular planes, and with a cylindrical rotor installed in the body, which is hollow, with an odd number of windows identical to the output windows of the case, and the total size windows in a circle is 180.

The disadvantage of such a pulsator is the presence of water hammer during the reproduction of a sinusoidal pulsating flow, which leads to the appearance of additional errors.

A device is known "Generator of variable fluid flow (options)" according to patent RU No. G01F 25/00, publ. 02/20/08. Bull. No. 6 - [3], containing a cylindrical rotor connected to the motor shaft, a cylindrical stator with two output slots along the generatrix of the cylinder on diametrically opposite sides associated with the pipelines. The rotor speed is changed through a gearbox connected to the control unit. To obtain various characteristics of the forms of variable flow, the removable rotor of the variable flow generator is truncated by various ruled surfaces bounded by guide curves according to the considered equations.

However, this device generates oscillations of the fluid flow, which are difficult and time-consuming to regulate in the oscillatory circuit.

The known device "Pulsator B.S. Lobanova (options) "according to patent RU No. 2240449, F15B 21/12, publ. 11/20/04 - [4]. It contains a housing with a discharge, supply and drain channels and a working chamber communicating with the drain channel, a rotating rotor with deflectors installed in the working chamber of the housing, supply nozzles communicating with the supply channel, receiving nozzles coaxial with them, communicating with the discharge channel, this nozzle with its end holes communicate with the working chamber of the housing, and the rotor deflectors, made in the form of blades, periodically interact with the working jet in order to form a working torque, leading about in rotation of the rotor.

However, this pulsator is characterized by high energy costs when creating pulsating flows of the working medium, since the drain and outlet channels at the output of the pulsator do not form an oscillating circuit to control the limited mass of liquid. This embodiment of the device provides difficultly controlled parameters of the fluid flow in the oscillatory circuit.

Closest to the claimed invention and coinciding with its purpose is the "Variable flow generator" according to the author's certificate of the USSR No. 637722, G01F 25/00, publ. 12/15/78. Bull. No. 46 - [5], designed to determine the dynamic characteristics of flowmeters. This device contains a rotor in the form of a cylinder truncated by a plane at an angle to its longitudinal axis, a hollow cylindrical stator with a rectangular slot along the generatrix of the cylinder on diametrically opposite sides. The rotor is connected to the motor shaft. The internal stator cavity is connected to an inlet pipe supplying a controlled medium. and through the slots it communicates with the segments of two pipelines, in one of which a test flowmeter is installed. The other ends of the pipelines are connected to the outlet piping through a throttle device.

The disadvantage of this generator is the possibility of its use only for the study of the sinusoidal shape of the pulse.

The technical result to which the claimed invention is directed is to expand the ability to control flow pulsations with various laws.

The technical result is achieved by the fact that in a pulsating flow generator containing a hollow rotor with output windows, connected to the shaft of the first engine and controlled by a control unit, a cylindrical stator with an inlet pipe and two output windows made diametrically opposite on its surface and connected to the output pipelines, new is that the output pipelines are interconnected by an additional pipeline, in which a regulator of the flow cross section is installed, made with zhnosti alternately overlap of these pipelines. The regulator of the flow cross section is made in the form of a piston with the possibility of rotational movement, the ends of which are protruding into the pipelines, truncated and oriented relative to each other by 90 °, ensuring the overlap of the pipelines in antiphase, while the piston is connected by means of a coupling to the shaft of the second engine controlled by the unit management. The flow cross-section regulator is made in the form of a piston with the possibility of reciprocating and rotational movement, the ends of which are protruding into the pipelines with the outlet pipelines overlapping in antiphase, the piston being connected to the shaft of the second engine controlled by the control unit.

The invention is illustrated in figures 1 and 2, where:

Figure 1 - regulator of the flow cross section with a rotational movement of the piston;

Figure 2 - regulator flow passage with reciprocating and rotational movement of the piston.

1 - rotor; 2 - stator; 3 - inlet pipeline; 4 - the first pipeline; 5 - the second pipeline; 6 - case; 7 - coupling; 8 - gear; 9 - the first engine; 10 - control unit; 11 - a piston; 12 - piston rods; 13 - an additional pipeline; 14 - coupling; 15 - second engine, 16 - piston; 17 - piston rods.

The pulsating flow generator contains a rotor 1 connected by a gearbox 8 and a coupling 7 to the shaft of the first engine 9. The rotor 1 is hollow and has windows located at different levels. The rotor shaft 1 is installed in the bearings of the generator housing 6, mounted in the stator 2, and the rotor 1 is removable and can be disconnected from the stator 2, as well as from the motor shaft 9 using the coupling 7. The speed of the rotor 1 is changed through a gearbox 8 connected with a control unit 10, to which the first motor 9 is electrically connected. The cylindrical stator 2 is a cylinder with input and two output windows. The output windows of the stator are located along the generatrix of the cylinder at different levels. The input window of the stator 2 is connected to the input pipe 3, its output windows are connected to the first 4 and second 5 pipelines, respectively.

The controlled fluid through the inlet pipe 3 enters the cavity of the stator 2. Depending on the alignment of the windows of the rotor 1 with the windows of the stator 2, the liquid passes through the output pipes 4 and 5. In this case, the fluid flow is determined by the area of the window that is not currently blocked by the rotor 1.

The maximum flow rate of the liquid in the outlet pipe is achieved by completely combining one of the windows of the rotor 1 with the window of the stator 2, and the minimum by completely overlapping the window of the stator 2. To obtain flow pulsations with different laws of change, rotors 1 with various forms of windows are used, for example, in the form different polygons, such as a rectangle, square, parallelogram, trapezoid, etc.

The ripple frequency is determined by the speed of rotation of the rotor 1, and the amplitude is determined by the flow rate. Due to the fact that the total area of the conditional passage of the windows remains constant, a pressure drop in the inlet pipe does not occur, which minimizes distortions in the shape and amplitude of flow fluctuations and improves the operating characteristics of the generator.

To obtain smoothly changing flow pulsations with different laws of change and to prevent water hammer, the windows of the rotor 1 are located at different levels, and the levels of the windows of the rotor 1 correspond to the levels of the windows of the stator 2.

The generation of fluid flow oscillations in this way is unregulated. In order to control the flow pulsations of more complex shapes, the output pipelines 4 and 5 are interconnected by an additional pipe 13, in which a flow passage regulator is installed, made in the form of a piston 11 with the possibility of rotational movement, the ends of which 12 are made protruding into the pipelines, truncated and oriented to each other relative to each other by 90 ° (Fig. 1) or in the form of a piston 16 with the possibility of reciprocating and rotational movement, the ends of which 17 are made protruding into the pipelines with overlapping thiy output pipelines in antiphase (figure 2).

The flow cross-section controller, shown in figure 1, is a piston 11 with two truncated rods 12 at the ends, which are made protruding into the output pipelines with the possibility of alternate overlapping of these pipelines. The piston 11 is connected through a clutch 14 to the shaft of the second engine 15 and is controlled by the control unit 10.

The flow cross-section controller, shown in figure 2, is made in the form of a piston 16, making a reciprocating and rotational movement in an additional pipe 13, which connects two output pipe 4 and 5 of the pulsating flow generator. The piston 16 is equipped with two protruding rods 17 in the output 4 and 5 pipelines with the possibility of sequentially overlapping these pipelines, while they periodically block the output pipelines in antiphase.

The pulsating flow generator operates as follows.

The control unit 10 sets the rotational speed of the shaft of the first 9 and second engines 15. When the shaft of the engine 9 is rotated with a cylindrical rotor 1 mounted on it, the windows of the rotor 1 periodically coincide with the output windows of the stator 2, and the moment the windows are combined in the first and second pipelines 4 and 5 is in antiphase, i.e. when one of the windows of the rotor 1 is fully combined with the window of the outlet pipeline, the window of the other pipeline is completely closed at this point in time. This is achieved by fully combining the windows of the stator 2 with the windows of the rotor 1. Thus, if the area of one window of the stator 2 increases, then the area of the other window decreases and vice versa.

Choosing the rotor 1 with various forms of its windows, change the shape of the variable generated flow. To replace the rotor 1, the coupling 7 is disconnected from the shaft of the engine 9, and then the housing 6 is also disconnected. The rotation frequency of the rotor 1 is changed by a gearbox 8 connected to the control unit 10.

Simultaneously with the rotor 1 is carried out and the rotation of the piston 11 in the additional pipe 13 (figure 1). The opposite overlapping rods 12 of the piston 11 allows you to adjust the fluid flow in the output pipes 4 and 5 in antiphase, as well as generate complex shapes of pulses of fluid flow in the oscillatory circuit.

Simultaneously with the rotor 1 performs a reciprocating and rotational movement of the piston 16 mounted in the additional pipe 13 (figure 2). The opposite overlapping rods 17 of the piston 16 allows you to adjust the fluid flow in the output pipes 4 and 5 in antiphase.

Thus, a pulsating flow generator is proposed in which the expansion of the possibilities for controlling flow pulsations with various laws is carried out by introducing a flow cross-section regulator made in the form of a piston with the possibility of sequentially blocking the output pipelines of the hydraulic circuit, while the solution of the device is simple in execution, simple and reliable in operation.

Claims (3)

1. A pulsating flow generator comprising a hollow rotor with output windows, connected to the shaft of the first engine and controlled by a control unit, a cylindrical stator with an inlet pipe and two output windows made diametrically opposite on its surface and connected to the output pipelines, characterized in that the output pipelines are interconnected by an additional pipeline, in which a flow cross-section regulator is installed, made with the possibility of sequentially overlapping these pipes wires. 2. The pulsating flow generator according to claim 1, characterized in that the regulator of the flow passage is made in the form of a piston with the possibility of rotational movement, the ends of which are protruding into the pipelines, truncated and oriented relative to each other by 90 °, providing overlapping pipelines in antiphase, wherein the piston is connected by means of a clutch to the shaft of the second engine controlled by the control unit. 3. The pulsating flow generator according to claim 1, characterized in that the regulator of the flow passage is made in the form of a piston with the possibility of reciprocating and rotational movement, the ends of which are protruding into the pipelines with the outlet pipelines overlapping in antiphase, while the piston is connected using couplings with a shaft of a second engine controlled by a control unit.

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