RU2705695C1 - Method of flow ejection and device for its implementation - Google Patents

Abstract

FIELD: technological processes.

SUBSTANCE: invention relates to jet equipment and can be used in many industries to increase degree of compression of flow by its ejection. Ejecting flow is supplied through active nozzle directly into radial slot gap on walls of which there are alternating annular zones of rarefaction with continuous flow of ejection flow, ejected flow is fed directly into the area of one or several annular rarefaction zones formed coaxially to the ejecting flow, the mixture of the ejecting and one or several ejected streams obtained in the radial-slot gap is removed from the radial-slit gap beyond the limits of the last annular zone of rarefaction. In the device for implementing the method, the annular channels are located within the alternating annular rarefaction zones alternately in the main, then in the reflecting walls of the radial-slot gap to the coaxially active central nozzle. Width of cross section of annular channel in radial direction does not exceed width of cross-section corresponding to this annular channel annular rarefaction zone, and the distance between the adjacent annular channels in the main and reflecting walls in the radial direction is approximately equal to the width of adjacent annular rarefaction zones corresponding to said annular channels.

EFFECT: increased rarefaction of ejected flow and increased efficiency of ejector.

5 cl, 3 dwg

Description

The invention relates to inkjet technology and can be used in many industries to increase the degree of compression of the stream by ejecting it.

It is widely known that when a flow is turned around, for example, in a bent pipe, or when an obstacle flows around it, a cavity is formed that helps to reduce the pressure in the zone of its contact with the wall due to an increase in speed due to a decrease in the cross section of the flow in this zone. In the book: Chuprakov Yu.I. Hydraulic actuator and means of hydraulic automation: A textbook for universities in the specialty "Hydraulic actuator and hydraulic automation". M. Engineering, 1979 - 232 p. The flow flow in a narrow slotted gap (small with respect to the nozzle cross-section by the gap between two walls) is considered when the stream is fed into the radial-slotted gap through an active central nozzle located at right angles to the planes of the walls. The stream flowing from the active nozzle into the radial slot gap formed by two walls, of which the main wall contains an active central nozzle for supplying the flow, and the reflecting wall is located relative to the main one with a small gap with respect to the nozzle cross section, forms a gap in this gap divergent flow. It is known that when the flow is turned from the active central nozzle to the radially slotted gap during the divergent flow past the edge of the active nozzle, an annular rarefaction zone is formed. The flow in the gap can be either tear-off or continuous. However, in this method, the kinetic energy of the flow in a narrow slot gap is not used for ejection.

It is known the flow in a narrow slotted gap (Cherepanov A.P. Inkjet logic devices for automatic orientation of flat parts during assembly. Thesis for the degree of candidate of technical sciences. Irkutsk 1993. - 158 pp.). Investigations carried out when applying a stream under pressure through a central nozzle to a small radial-gap gap between closely spaced walls with respect to its cross section, of which the reflecting wall is continuous, and the main wall contains a central nozzle for supplying a stream and a number of holes for diverting the stream from the gap located at different radii from the central nozzle, it was shown that the excess pressure of the diverging stream during its continuous flow in the radial-gap gap creates alternating ring rings in it e rarefaction zones and annular zones of increased pressure. The presence of rarefaction and increased pressure in alternating annular zones was recorded using U-shaped pressure gauges.

Known methods of ejection flow (USSR Author's Certificate No. 338687, MKI F04F 5/14, Publ. 05/15/1972, Bull. No. 16) in which the ejection stream is fed into the active central nozzle in the main wall under pressure, mix it with the ejected stream supplied into the low-pressure cavity and the mixture is diverted through a radial-gap gap formed between the main and reflective walls, the value of which leads to pressure pulsation in the mixing zone, it is reduced due to the conical section of the outlet channel in communication with the low-pressure cavity , a single-stage feed of the ejected flow does not allow an increase in vacuum.

Known methods of ejection flow (Patent US 1296567 A (Suczek) 03/04/1919) in which the ejection stream is fed into the active nozzle under pressure, mix it with the ejected stream, which is fed through the annular zone and the mixture is removed through the radial-gap gap formed between the walls moreover, the size of the gap controls only the flow of the ejection flow before entering the radially slotted gap, and the ejected flow is fed into the annular channel simultaneously from two sides, while only one-stage flow of the ejected flow is provided, h on makes it impossible to increase the negative pressure.

Known methods of ejection flow (USSR Author's Certificate No. 1019114, MKI F04F 5/42, Publ. 23.05.83, Bull. No. 19), in which the ejected stream is fed into the active nozzle under pressure, mixed with the ejected stream and the mixture is removed through radially - a gap gap formed between the main wall and the reflecting wall, the ejection stream is fed into the mixing chamber, it is swirled in the mixing chamber, into which the ejected stream is sucked through the passive central channel and mixed with the ejected stream. The mixed stream through the central nozzle is fed into the radial-gap gap between the main and reflective walls to convert the kinetic energy of the mixed stream into pressure. Thus, in the known method, kinetic energy is spent not only on the ejection of the flow, but also on its turbulence in the mixing chamber and in the Central hole. Further, kinetic energy is spent on reducing the swirl by separation (rupture) of the flow by an annular channel in the central hole, into which a part of the mixed flow is additionally supplied from the radial-slot gap through the pipeline, the mixed flow is converted to pressure in the radial-gap diffuser between the main and reflective walls. As a result, the kinetic energy of the flow is spent first on creating a turbulence, and then on its decrease in the central channel and in the radial-slot diffuser between the main and reflecting walls. The single-stage supply of the ejected flow also does not allow the increase in vacuum.

Known methods of ejection flow (Patent US 4523894 A MKI F04F 5/00, 06/18/1985) in which the ejection stream is fed into the active nozzle under pressure, mixed with the ejected stream, which is fed through the annular zone and the mixture is withdrawn through a radial-gap gap, formed between the walls, and the annular zone for the removal of the ejected stream is located only on the side of the reflective wall, while the largest vacuum, as you know, creates an annular zone located as close to the Central channel from the side of the main wall therefore, a single-stage supply of the ejected flow from the side of the reflecting wall does not allow the increase in vacuum.

The analysis showed that none of the known methods of flow ejection and devices for its implementation use alternating rarefaction zones formed during a continuous flow of the stream between the walls of the radial-gap gap, therefore, these methods cannot increase the rarefaction of the ejected stream.

As a prototype adopted the closest in technical essence and the achieved result, the method of flow ejection and a device for its implementation (Patent US 5584668 A (Volkmann) MKI F04F 5/16; F04F 5/22; F04F 5/00; F04F 005/00 17.12. 1996), which consists in feeding the ejection stream under pressure through the active central nozzle into the radial-gap gap and mixing with the ejected flows, which are sucked into the radial-gap gap through the annular channels with the outlet of the mixed stream through the radial-gap gap between the main and reflecting walls behind P Gödel last annular channel. The known method has several mixing zones of several ejected streams, which in comparison with analogues has the advantage. However, in the known method, with the two-sided supply of ejected flows into the radially slotted gap, the annular channels, both on the main and on the reflecting walls, are arranged towards each other at equal distances from the central channel. Considering that the diverging flow pressure in the radial slot gap creates alternating annular rarefaction zones and annular zones of increased pressure, the opposing arrangement of the annular channels at equal distances from the central supply channel is inefficient, since where one of the annular channels, for example, from the main wall coincides with the annular rarefaction zone, the oppositely located annular channel from the side of the reflecting wall in this case coincides with the annular zone of increased pressure, which yatstvuet ejected flow from this annular channel, however, a part of the annular channel is not activated to create a vacuum. In addition, if the mixed flow at the outlet of the last annular rarefaction zone immediately outside it enters the pressure zone, this also prevents an increase in rarefaction.

Thus, the location of the annular channels at equal distances from the central channel without taking into account the alternating annular rarefaction zones and annular zones of increased pressure in the radial-gap gap, using the known method and device for its implementation, it is not possible to increase the vacuum and increase the performance of the ejector.

The aim of the invention is to increase the rarefaction of the ejected stream and increase the productivity of the ejector.

The technical result of the invention is achieved by placing annular channels for ejected flows in alternating annular rarefaction zones formed during a continuous flow between the walls of the radial-gap gap.

Description of drawings:

FIG. 1. Device for implementing the method of ejection flow.

FIG. 2 - Main dimensions and parameters.

FIG. 3 - Dependence of rarefaction on the size of the gap between the walls at overpressure in the central channel from R _And = 1 kg / cm ² to R _And = 3 kg / cm ² .

The flow ejection method is carried out by supplying the ejection flow under pressure through the active central nozzle to the radial-gap gap, the diverging ejection flow into the radial-gap gap is fed in a continuous flow, which between the walls of the radial-gap gap coaxially to the central nozzle creates one or more alternating annular rarefaction zones , the ejected stream is fed directly to the region of one or more alternating annular discharge zones formed coaxially to the ejected stream so that:

- in the first case, the first ejected stream is sucked into the first annular rarefaction zone through the first annular channel located on the main wall;

- in the second case, the second ejected stream is sucked into the second annular rarefaction zone through the second annular channel located on the reflective wall and mixed with the previous mixed stream;

- in the third case, the third ejected stream is sucked into the third annular rarefaction zone through the third annular channel located in the main wall and mixed with the previous flows;

- with further flow, subsequent ejected flows are sucked into the annular rarefaction zones alternately on the reflective, then on the main wall, through annular channels located alternately on the reflective, then on the main wall and then the entire mixed stream is diverted from the radial-gap gap outside the last annular rarefaction zone.

The width of the alternating annular rarefaction zones in the radial direction is changed, for example, by changing the pressure of the ejection flow, the magnitude of the radial-gap gap, which is set within the formation of a continuous flow in the radial-gap gap.

The continuous flow of the stream is set by the value of the radial-gap gap in the range from 0.1 mm to 1.0 mm.

The analysis of the prior art showed that in the known methods of flow ejection and in devices for its implementation, alternating annular rarefaction zones are not used, which are formed during a continuous flow of the flow between the walls of the radial slot gap, therefore, using known methods and devices for ejecting the flow, it is not possible to increase the rarefaction of the ejected flow.

By comparing the prior art it was found that none of the closest analogues and prototype in terms of the set of features identical to all the features of the claimed technical solution does not increase the rarefaction of the ejected stream, which meets the criteria of "novelty". Search results for known technical solutions have shown that the distinguishing features of the claimed method and its implementation do not follow explicitly from the presented analogues, prototype and known technical solutions in related fields of technology. The prior art also did not reveal the essential features of the proposed solution necessary to achieve the claimed technical result. Therefore, the claimed invention meets the condition of patentability "inventive step".

The flow ejection method is illustrated by an example of a device for its implementation.

A device for implementing the method of flow ejection comprises a main wall 1 and a reflecting wall 2 (fixing the walls 1 and 2 to each other in the figures of Fig. 1 and Fig. 3 is not shown). Walls 1 and 2 are fixed relative to each other and form a radial-gap gap 3, the value of h of which is selected so that between the walls 1 and 2 a continuous flow of the diverging ejection stream 5 is provided. The active central nozzle 4 is located in the main wall 1 and serves for supplying the ejection stream 5 under an excess pressure P _AND into the radially slotted gap 3. To increase the velocity of the ejection stream and create a continuous flow, the value h of the radial slotted gap 3 is selected less than river section of the active central nozzle 4. This device used three ejected stream P _B1 , P _B2 and P _B3 . The annular channel 6 is located in the main wall 1 of the coaxially active central nozzle 4 and is connected by a cavity 7 to the hole 8 for suction of the ejected stream P _B1 into the radially slotted gap 3 through the patch panel 9. The annular channel 10 is located in the reflective wall 2 coaxially with the central active nozzle 4 and connected by a cavity 11 to the hole 12 for suction of the ejected stream P _B2 into the radially slotted gap 3 through the patch panel 13. The annular channel 14 is located in the main wall 1 of the coaxially active central nozzle 4 and is connected by a cavity 15 to the hole 16 for suction of the ejected stream P _B3 into the radially slotted gap 3 through the switching panel 9. Thus, the ejected flows are interconnected by a switching panel 9 located on the free side of the main wall 1 and located on the free side of the reflecting wall 2 by the patch panel 13. The patch panels 9 and 13 are sealed with rings 17, which serve to seal the cavities 7, 11, 15.

A device for implementing the method of ejection flow works as follows. In an uninterrupted flow between walls 1 and 2, the ejection flow 5 under excess pressure P _And when fed into the active central nozzle 4 at the exit from it, detaches from the edge 18, a stream 19 is created in the radial-slot gap 3, which hits a continuous reflecting wall 2, in the center of the jet 19, a zone of reduced pressure 20 is formed. The pressure in the radial-gap gap 3 is lower than the pressure of the ejection stream 5, therefore, after it is detached from the edge 18 in the radial-gap gap 3, a diverging continuous flow of the stream is formed. In the annular section 21, the flow velocity increases, the first narrowing of the flow 22 from the side of the main wall 1 is formed, and the first annular rarefaction zone 23 is created, which, through the annular channel 6 and the cavity 7, sucks the ejected flow P _B1 from the hole 8 into the radial-gap gap 3, where P _B1 ejection stream mixes with the entraining stream 5. Under the influence of the first annular dilution zone 23, the mixed flow is pressed against the main wall 1 is formed the second flow restriction 24 and the reflecting walls 2 of the second annular zone is created azrezheniya 25 which through an annular channel 10 and the cavity 11 draws the ejected stream P _B2 of the opening 12 in a radially-slotted gap 3, where the ejection stream P _B2 is mixed with the flow in the gap radially slit 3. Under the influence of the second annular dilution zone 25 mixed stream presses against the reflecting wall 2, a third narrowing of the flow 26 is formed. From the side of the main wall 1, a third annular rarefaction zone 27 is created, which, through the annular channel 14 and the cavity 15, sucks the ejected flow P _B3 from the hole 16 into the radial-gap gap 3, in otorom the ejected stream P _B3 is mixed with the stream in the radial-gap gap 3. Thus, the ejected flows P _B1 , P _B2 and P _B3 , mixed in the three annular zones 23, 25 and 27, form a single mixed stream 28, which is behind the last annular zone vacuum extends beyond the radial-gap gap 3.

The maximum rarefaction of the ejected flow is created when the ejected flows P _B1 , P _B2 and P _B3 from the annular channels 6, 10, 14 are completely absorbed in the annular rarefaction zones 23, 25, 27. For this, in the radial direction, the width from the annular channel 6, 10 , 14 should be less than the width b of the annular rarefaction zone 23, 25, 27 conjugated with it, the distance a between the adjacent annular channels 6, 10, 14 is approximately equal to the width b of the adjacent annular rarefaction zones 23, 25, 27 (Fig. 2) .

In the radial direction, the length L and width b of the annular rarefaction zones 23, 25, 27 can vary for a number of reasons, for example, when the ejection and ejection media are inhomogeneous, the pressure of the ejection flow changes, or when choosing the optimal value h of the radial-gap gap 3 to create the continuous flow of the diverging stream, therefore, the width from the annular channels 6, 10, 14 should be set no more than the width b of the corresponding annular rarefaction zone 23, 25, 27 (Fig. 2).

Figure 3 shows, by way of example, what value h of the radial slot gap 3 with a continuous flow can be selected to achieve the required ejector vacuum depending on the pressure in the central channel 4. The graph (Fig. 3) shows that a continuous flow of a diverging ejection flow is created when the value of h is from 0.1 to 1.3 mm of the radial-gap gap 3, which is determined by the relative position of the walls 1 and 2 and the magnitude of the overpressure in the supply channel 4. For example, with a gap h = 0.3 mm and overpressure P _AND = 1.0 kg / m ² dilution value is 0.37 kg / cm ² and at a pressure P h ₌ 3.0 kg / cm ² dilution value is 0.45 kg / cm ^2. This means that with an increase in excess pressure in the supply channel 4, the vacuum in the annular vacuum zones 23, 25, 27 increases. As can be seen from the graph, if the radial-gap gap 3 becomes more than h> 1.3 mm, then at an excess pressure P _И = 1.0 kg / cm ^{2, the} vacuum in the annular zones 23, 25, 27 decreases to zero. With a further increase in the gap, the continuous flow of the flow passes into the separated flow, and in the annular zones 23, 25, 27 the vacuum changes to overpressure.

Thus, the rarefaction of the ejected flow in the annular rarefaction zones 23, 25, 27 can be adjusted (lower or higher) in one or more ways, including:

- a change (decrease or increase) in the overpressure P _{AND of} flow 5 in the active central nozzle 4;

- a change (decrease or increase) in the cross-sectional area of the central nozzle 4;

- a change (decrease or increase) in the cross-sectional area of the radially slotted gap 3 by increasing the radius R of the main 1 and reflecting 2 walls;

- a change (decrease or increase) in the value of h of the radially slotted gap 3 to the extent that it provides an uninterrupted flow stream;

- a change (decrease or increase) in the number of annular rarefaction zones and the corresponding number of ejected flows and annular channels in the range from 1 to n.

To reduce the suction resistance of the ejected flow, the annular channel 6 in the main wall and the annular channels 10, 14 in the reflecting wall in the radial direction can be, for example, inclined, like an annular channel 14, or curved, like an annular channel 10, as shown in the figure (Fig. . 2).

Testing and comparison of the proposed method of flow ejection and the device for its implementation with the well-known single-stage ejector based on the Laval nozzle, with equal diameters of the active nozzles and equal excess air flow pressures, showed that the proposed method and device with one annular rarefaction zone create a rarefaction in this annular zone 4 times higher than the known ejector.

The proposed method of flow ejection and a device for its implementation can reduce the loss of kinetic energy, increase the rarefaction of the ejected stream and increase the performance of the ejector.

Claims (5)

1. A method of flow ejection, which consists in supplying an ejection flow under pressure through an active central nozzle into a radially slotted gap between the main and reflective walls, suction of one or more ejected flows into a radially slotted gap through one or more annular channels, in mixing the ejection and ejected flows and in the outlet of the mixed flow through the radial-gap gap outside the last annular channel, characterized in that the ejected stream in the radial-gap gap serves In a continuous flow, the ejected flow is fed directly to the region of one or more coaxially ejected flow of alternating annular rarefaction zones formed when the ejected flow diverges in the radial slot gap, while the first ejected flow is sucked into the first annular rarefaction zone through the first annular channel located on main wall; the second ejected stream is sucked into the second annular rarefaction zone through a second annular channel located on the reflective wall and mixed with the previous mixed stream; the third ejected stream is sucked into the third annular rarefaction zone through the third annular channel located in the main wall and mixed with the previous flows; subsequent ejected flows are sucked through alternating annular rarefaction zones alternately, then on the reflective, then on the main wall into the annular channels, also located alternately on the reflective, then on the main wall, and then the entire mixed stream is diverted from the radial-gap gap outside the last annular rarefaction zones. 2. The method according to p. 1, characterized in that the width of the alternating annular rarefaction zones in the radial direction is changed, for example, by changing the pressure of the ejection flow and the magnitude of the radial-gap gap, and the magnitude of the radial-gap gap is set within the formation of a continuous flow in the radially gap gap. 3. The device for implementing the method according to claim 1, containing the main and reflecting walls forming a radial-gap gap, an active nozzle for supplying an ejection flow under pressure located on the main wall, while the radial-gap gap is less than the cross section of the active central nozzles; openings for suction of the ejected flow, one or more annular channels located in the main wall of the coaxially active central nozzle, connected by cavities with openings for suction of the ejected flows in the radially slotted gap through the patch panel of the main wall, one or more annular channels located in the reflective wall coaxially to the central active nozzle, connected by cavities with holes for suction of ejected flows into the radial-slot gap through the switching reflecting wall panel, characterized in that the annular channels are located within the annular alternating underpressure zones alternately in the core, the walls in the reflective radially-slit gap coaxially active central nozzle. 4. The device according to p. 3, characterized in that the width of the cross section of the annular channel in the radial direction does not exceed the width of the cross section corresponding to this annular channel of the annular rarefaction zone. 5. The device according to p. 3, characterized in that the distances between adjacent annular channels in the main and reflecting walls in the radial direction are approximately equal to the width of adjacent alternating annular rarefaction zones corresponding to these annular channels.

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