Fluid conveying device and fluid conveying method

Abstract

The present invention provides a fluid conveying device that conveys a fluid to be transported in a manner that allows it to reach a target position with sufficient spread while suppressing unnecessary diffusion into the surroundings. [Solution] A circular first nozzle 11 from which the conveyed fluid is ejected is surrounded by an annular second nozzle 12. The conveyed fluid is ejected from the first nozzle 11 as a swirling flow, while an annular jet of the second fluid is ejected from the second nozzle 12, thereby creating a double jet where the swirling flow of the conveyed fluid is surrounded by the annular jet of the second fluid. This creates a low-pressure region at the center of the swirling flow ejected from the first nozzle 11, and the annular jet acts as an air curtain for the swirling flow, suppressing diffusion and allowing the conveyed fluid to proceed towards the target position. Compared to simply ejecting a straight jet of the conveyed fluid from a single nozzle, more conveyed fluid can be delivered to a greater distance.

Description

[Technical Field]

[0001] The present invention relates to a fluid conveying device that transports a fluid to be conveyed, such as a gas or liquid, to a target position in space. [Background technology]

[0002] A conveying device has been proposed that delivers a predetermined fluid to a target position by ejecting the fluid as a jet from a nozzle toward the target position. Such a transport device is disclosed in Japanese Patent No. 5846617, developed by the present applicant. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Patent No. 5846617 [Overview of the Initiative] [Problems that the invention aims to solve]

[0004] Conventional conveying devices for conveyed fluids, as shown in the aforementioned patent document, eject the conveyed fluid as a laminar jet from a first nozzle, while ejecting a second fluid as an annular jet from an annular second nozzle arranged around the outer circumference of the first nozzle. The annular jet of the second gas functions as an air curtain, suppressing the diffusion of the conveyed fluid to the target distance and enabling localized conveyance of the conveyed fluid.

[0005] Regarding the transport of such fluids, depending on the intended use of the fluid, it may be desirable to give the fluid jet a widthwise spread, that is, a spread in all directions perpendicular to the direction of jet propagation, so that the fluid reaches the entire target area evenly, even if the target location is larger than the size of the nozzle.

[0006] However, even in such cases, in order to ensure that a sufficient amount of the conveyed fluid reaches the target position, it is essential to use a conveying method that suppresses the diffusion of the conveyed fluid during conveyance, as described in the aforementioned patent document. However, when attempting to suppress the diffusion of the conveyed fluid with conventional conveying devices, even after the jet has traveled a predetermined distance and the diffusion-suppressing effect on the conveyed fluid in the jet has disappeared, the degree to which the jet expands in the width direction due to diffusion is gradual, and it was not possible to rapidly expand the reachable range of the conveyed fluid in the jet.

[0007] To further increase the widthwise spread of the transported fluid jet and expand the reachable range of the transported fluid, it is necessary to change conditions such as the jet ejection velocity in the transport device to shorten the distance at which the jet diffusion suppression effect is effective, thereby accelerating the start of the jet's widthwise spread due to diffusion. However, if the jet diffusion suppression effect is lost too early, the diffusion of the transported fluid, i.e., mixing with the surrounding fluid, will also proceed quickly, resulting in a decrease in the proportion of the transported fluid in the jet that reaches the target position.

[0008] Thus, it was difficult to achieve both ensuring the amount of fluid being transported reaches the target position by suppressing diffusion and expanding the jet's reach by widening the fluid jet.

[0009] The present invention has been made to solve the aforementioned problems, and aims to provide a fluid conveying device and a fluid conveying method applicable thereto, which conveys a fluid to be conveyed in a manner that allows it to reach a target position with sufficient spread while suppressing unnecessary diffusion into the surroundings. [Means for solving the problem]

[0010] The fluid conveying device disclosed in the present invention comprises a first nozzle arranged as a circular opening and capable of ejecting a fluid to be conveyed on the front side of the opening, and a second nozzle arranged as an annular opening surrounding the outside of the first nozzle and capable of ejecting a predetermined second fluid, wherein the first nozzle ejects the fluid to be conveyed as a swirling flow that moves toward the front side of the opening while rotating around a virtual central axis extending toward the front side of the opening, and the second nozzle ejects the second fluid toward the front side of the opening as an annular jet surrounding the fluid to be conveyed.

[0011] As described above, according to the disclosure of the present invention, a circular first nozzle from which the conveyed fluid is ejected is surrounded by an annular second nozzle. The conveyed fluid is ejected from the first nozzle as a swirling flow, while an annular jet of the second fluid is ejected from the second nozzle, thereby obtaining a double jet where the swirling flow of the conveyed fluid is surrounded by the annular jet of the second fluid. This creates a low-pressure region at the center of the swirling flow ejected from the first nozzle, making it difficult for the conveyed fluid to diffuse. At the same time, the annular jet acts as an air curtain for the swirling flow, suppressing diffusion and allowing the conveyed fluid to proceed towards the target position. Compared to simply ejecting a straight jet of the conveyed fluid from a single nozzle, more conveyed fluid can be delivered to a greater distance.

[0012] Furthermore, as each fluid travels the desired distance, the diffusion suppression effect on the swirling flow by the annular jet and low-pressure region weakens. This increases the degree of spread of the swirling fluid being transported, allowing the jet width of the dual jets in the straight-line direction to be expanded. This enables the transported fluid to efficiently reach the entire range set as the target position, and allows for effective utilization of the functions of the transported fluid at the target position. [Brief explanation of the drawing]

[0013] [Figure 1] This is an explanatory diagram of the usage state of a fluid conveying device according to one embodiment of the present invention. [Figure 2] This is a schematic diagram illustrating the configuration of a fluid transport device according to one embodiment of the present invention. [Figure 3] This is an explanatory diagram of the ejection state of a double jet from a fluid conveying device according to one embodiment of the present invention. [Figure 4] This is an explanatory diagram of the arrangement of the fluid transport device in Embodiment 1 of the present invention. [Figure 5] This is a partially omitted rear view of the double nozzle portion of the fluid transport device in Embodiment 1 of the present invention. [Figure 6] This is a partially omitted longitudinal cross-sectional view of the double nozzle portion of the fluid transport device in Embodiment 1 of the present invention. [Figure 7] This diagram illustrates the ejection state of the swirling flow in the double jet ejected from the fluid transport device in Embodiment 1 of the present invention at a velocity ratio γ1 = 0.25. [Figure 8] This diagram illustrates the ejection state of the swirling flow in the double jet ejected from the fluid transport device at a velocity ratio γ1 = 0.5 in Embodiment 1 of the present invention. [Figure 9] This diagram illustrates the ejection state of the swirling flow in the double jet ejected from the fluid transport device in Embodiment 1 of the present invention at a velocity ratio γ1 = 0.75. [Figure 10] This diagram illustrates the ejection state of the swirling flow in the double jet ejected from the fluid transport device in Embodiment 1 of the present invention at a velocity ratio γ1 = 1.0. [Figure 11] This diagram illustrates the ejection state of the swirling flow in the double jet ejected from the fluid transport device in Embodiment 1 of the present invention at a velocity ratio γ2 = 0.25. [Figure 12] This diagram illustrates the ejection state of the swirling flow in the double jet ejected from the fluid transport device in Embodiment 1 of the present invention at a velocity ratio γ2 = 0.5. [Figure 13] This diagram illustrates the ejection state of the swirling flow in the double jet ejected from the fluid transport device in Embodiment 1 of the present invention at a velocity ratio γ2 = 1.0. [Figure 14] This diagram illustrates the ejection state of the swirling flow in the double jet ejected from the fluid transport device in Embodiment 1 of the present invention at a velocity ratio γ2 = 1.5. [Figure 15] This diagram illustrates the ejection state of the inner circular jet in a double jet without a swirling velocity component, as a comparative example to the double jet from a fluid conveying device in Embodiment 1 of the present invention. [Figure 16] These are explanatory diagrams illustrating the ejection states of four examples of the first group of double jets ejected from a fluid transport device in Embodiment 1 of the present invention, with varying velocity ratios γ1 and γ2. [Figure 17] These are explanatory diagrams illustrating the ejection states of four examples from the second group of double jets ejected from the fluid transport device in Embodiment 1 of the present invention, with varying velocity ratios γ1 and γ2. [Figure 18] These are explanatory diagrams illustrating the ejection states of four examples from the third group of double jets ejected from the fluid transport device in Embodiment 1 of the present invention, with varying velocity ratios γ1 and γ2. [Figure 19] These are explanatory diagrams illustrating the ejection states of four examples of the fourth group of double jets ejected from a fluid transport device in Embodiment 1 of the present invention, with varying velocity ratios γ1 and γ2. [Figure 20] This graph shows the relationship between the velocity ratio of a double jet ejected from a fluid transport device in Embodiment 1 of the present invention, with varying velocity ratios γ1 and γ2, and the potential core length. [Figure 21] This graph shows the relationship between the velocity ratio and jet width of a double jet ejected from a fluid transport device in Embodiment 1 of the present invention, with varying velocity ratios γ1 and γ2. [Figure 22] This graph shows the velocity distribution on the nozzle central axis of a double jet ejected from a fluid transport device in Embodiment 1 of the present invention, with varying velocity ratios γ1 and γ2. [Figure 23] This is an explanatory diagram of the arrangement of the fluid transport device in Embodiment 2 of the present invention. [Figure 24] This diagram illustrates the ejection state of the swirling flow among the double jets ejected from the fluid transport device in Embodiment 2 of the present invention. [Figure 25] This graph shows the straight-line efficiency values ​​for each velocity ratio of the double jet ejected from the fluid transport device in Embodiment 2 of the present invention, with varying velocity ratios γ2. [Modes for carrying out the invention]

[0014] Hereinafter, a fluid conveying device according to one embodiment of the present invention will be described based on Figures 1 to 3. In this embodiment, an example of a fluid conveying device that conveys sterilized or otherwise treated clean air as the fluid to be conveyed to a target position (for example, near the user's body or face) in a typical indoor space will be described.

[0015] In the figures above, the fluid conveying device 1 according to this embodiment comprises an inner nozzle 21 having a circular opening at its tip as a first nozzle 11, an outer nozzle 22 arranged to surround the outer circumference of the inner nozzle 21 and having an annular opening at its tip as a second nozzle 12, a first fluid supply unit 30 that supplies the fluid to be conveyed to the inner nozzle 21, and a second fluid supply unit 40 that supplies the second fluid to the outer nozzle 22.

[0016] The internal nozzle 21 is a nozzle with a circular cross-section, and the circular opening at its tip is designated as the first nozzle outlet 11. The fluid to be transported is supplied from the first fluid supply unit 30 to the opening of the internal nozzle 21 opposite to the first outlet 12.

[0017] The first nozzle 11 is positioned as a circular opening at the tip of the inner nozzle 21, and the fluid to be conveyed can be ejected from the front side of this opening. The first nozzle 11 ejects the fluid to be transported as a swirling flow that moves toward the front of the opening while swirling around a virtual central axis that extends toward the front of the opening. The swirling flow of the conveyed fluid ejected from the first nozzle 11 has a velocity component that travels straight ahead towards the front of the opening, with a single ejection velocity U c , and other ejection velocities U as swirling velocity components s Each is given.

[0018] The outer nozzle 22 is a nozzle whose cross-section is circular with a larger diameter than that of the inner nozzle 21, and is arranged coaxially on the outer circumference of the inner nozzle 21. The annular opening region at the tip of the nozzle, located on the outer circumference side of the tip opening (first nozzle) of the inner nozzle 21, is designated as the second nozzle 12. The second fluid is supplied from the second fluid supply unit 40 to the opening of the outer nozzle 22 opposite to the second outlet 12.

[0019] The second nozzle 12 is positioned at the tip of the outer nozzle 22 as an annular opening surrounding the outside of the first nozzle 11, and is capable of ejecting a predetermined second fluid. The second nozzle 12 ejects the second fluid as an annular jet surrounding the fluid to be transported, towards the front of the opening. This annular jet of the second fluid is ejected towards the front of the opening at a predetermined ejection velocity U a It is set to be ejected.

[0020] The radial opening width of the annular opening forming the second nozzle 12 is set to be less than or equal to the diameter of the first nozzle 11. By making the opening width of the second nozzle 12 less than or equal to the diameter of the first nozzle 11, it is possible to suppress the diffusion of the swirling flow ejected from the first nozzle 11 by the ejected annular jet. More preferably, the annular width of the second nozzle 12 is less than or equal to half the diameter of the first nozzle 11. If the annular width of the second nozzle 12 is made larger than the diameter of the first nozzle 11, the influence of the annular jet from the second nozzle 12 will increase, which may adversely affect the straightness of the swirling flow from the first nozzle 11.

[0021] The first fluid supply unit 30 comprises a supply pipe 31 connected to the inner nozzle 21 so that the fluid to be conveyed flows in in a direction having a swirling velocity component along the inner circumference of the inner nozzle 21 and a velocity component moving straight toward the first outlet 11; a blower 32 that sends the fluid to be conveyed through the supply pipe 31; and an air purification device 33 that generates clean air to be conveyed from the room air and supplies it to the blower 32.

[0022] The second fluid supply unit 40 is configured to include a supply pipe 41 that is connected to the outer nozzle 22 so that the second fluid flows in in a direction that is straight toward the second outlet 12, and a blower 42 that sends indoor air as the second fluid through the supply pipe 41.

[0023] The first fluid supply unit 30 sets the supply state of the fluid to be conveyed by the blower 32 so that the ejection speed U of the fluid to be conveyed at the first ejection port 11 c 、U s satisfies the desired conditions. Also, the second fluid supply unit 40 sets the supply state of the second fluid by the blower 42 so that the ejection speed U of the second fluid at the second ejection port 12 a satisfies the desired conditions.

[0024] And the ejection speed U of the fluid to be conveyed from the first ejection port 11 c 、U s and the ejection speed U of the second fluid from the second ejection port 12 a are set to values that satisfy predetermined conditions in order to appropriately control the degree of diffusion of the fluid to be conveyed.

[0025] Specifically, for the speed ratio γ1 = U of one ejection speed U in the swirling flow of the fluid to be conveyed c and the ejection speed U of the jet flow of the second fluid a with respect to the ejection speed Uc, a γ1 = U a / U c is set to satisfy the condition of 0.25 ≦ γ1(= U a / U c ) ≦ 1

[0026] At the same time, for the speed ratio γ2 = U of one ejection speed U which is the straight - ahead speed component in the swirling flow of the fluid to be conveyed c and the other ejection speed U which is the swirling speed component s with respect to the ejection speed U c γ2 = U s / U s / U c is set to satisfy the condition of 0 < γ2(= U s / U c ) ≦ 1.5

[0027] ​​When the ejection velocity is set to satisfy these conditions, the annular jet ejected from the second nozzle 12 functions as a kind of air curtain, suppressing the diffusion of the conveyed fluid ejected as a swirling flow from the first nozzle 11. This keeps the conveyed fluid within the annular jet, creating a potential core (a region without mixing), and allows the conveyed fluid to be transported to the desired distance while suppressing its diffusion into the surrounding atmosphere, i.e., the room air.

[0028] In this way, by setting the optimal velocity ratio, the potential core can be maintained for a sufficient transport distance, such as about ten times the diameter of the first nozzle 11, thereby suppressing the diffusion of the swirling flow. The optimal velocity ratio for maintaining the swirling flow of the transported fluid within the annular jet and suppressing diffusion while transporting it to the target distance is U a / U c = 0.75.

[0029] Note U a / U c If it exceeds 1, the annular jet will not function adequately as an air curtain. Also, U a / U c If the value is less than 0.25, the transport distance over which diffusion can be suppressed becomes significantly shorter.

[0030] Next, the transport state of the transported fluid in the fluid transport device based on the above configuration will be described. As a premise, it is assumed that the transported fluid, which is sterilized clean air, can be continuously supplied by the air purification device 33 of the first fluid supply unit 30.

[0031] The clean air, which is the fluid to be conveyed, is continuously generated by the air purification device 33 of the first fluid supply unit 30 and supplied to the blower 32, which then sends it to the supply pipe 31. The fluid to be conveyed is then sent through the supply pipe 31 into the inner nozzle 21 from the opening opposite the first outlet 11 of the inner nozzle 21.

[0032] Based on the arrangement of the supply pipe 31 relative to the inner nozzle 21, the fluid being transported becomes a swirling flow within the inner nozzle 21, having a swirling velocity component along the inner circumference of the inner nozzle 21 and a velocity component traveling straight toward the first outlet 11.

[0033] Meanwhile, the second fluid, which is indoor air, is drawn into the blower 42 of the second fluid supply unit 40, and from this blower 42 through the supply pipe 41, it is sent into the annular space inside the outer nozzle 22 (the space between the outer cylinder of the outer nozzle 22 and the inner cylinder of the inner nozzle 21) from the opening on the opposite side of the second outlet 12 of the outer nozzle 22.

[0034] The swirling flow of the conveyed fluid entering the inner nozzle 21, which has both a swirling velocity component and a straight-line velocity component, continues to travel through the inner nozzle 21 and is ejected from the first outlet 11. This swirling flow of the conveyed fluid travels towards the front of the opening of the first outlet 11 while swirling around a virtual central axis that extends towards the front of the opening. Furthermore, the second fluid that enters the outer nozzle 22 travels through the outer nozzle and is ejected as an annular jet from the second nozzle 12 towards the front of the opening of the second nozzle 12.

[0035] In this way, a double jet, formed by the combination of the swirling flow of the conveyed fluid ejected from the first outlet 11 of the inner nozzle 21 and the annular jet of the second fluid ejected from the second outlet 12 of the outer nozzle 22, travels through the interior space.

[0036] The swirling flow of the conveyed fluid travels a predetermined distance while diffusion is suppressed by the formation of a potential core due to the protection of the annular jet and the low-pressure region created by the swirling flow. After passing the tip of the potential core, the swirling flow of the conveyed fluid, whose diffusion suppression effect weakens and which becomes more prone to diffusion, continues to travel with a greater degree of spread than before, until it reaches the target position T in a predetermined state of spread.

[0037] In this way, by suppressing the diffusion of the transported fluid, which is clean air, during its journey toward the target position T, a sufficient concentration (the proportion of the transported fluid in a unit area) can be ensured even upon reaching the target position T. Furthermore, the degree of swirling flow expansion can be increased near the target position T, allowing the transported fluid to reach the target position T with sufficient spread.

[0038] Thus, in the fluid conveying device according to this embodiment, an annular second nozzle 12 is arranged around a circular first nozzle 11 from which the conveyed fluid is ejected. The conveyed fluid is ejected from the first nozzle 11 as a swirling flow, while an annular jet of the second fluid is ejected from the second nozzle 12, thereby obtaining a double jet where the swirling flow of the conveyed fluid is surrounded by the annular jet of the second fluid. This creates a low-pressure region at the center of the swirling flow ejected from the first nozzle 11, making it difficult for the conveyed fluid to diffuse. At the same time, the annular jet acts as an air curtain against the swirling flow, suppressing diffusion and allowing the conveyed fluid to proceed towards the target position T. This extends the reach of the conveyed fluid compared to simply ejecting a straight jet of the conveyed fluid from a single nozzle.

[0039] Furthermore, as each fluid travels the desired distance, the diffusion suppression effect on the swirling flow by the annular jet and low-pressure region weakens. This increases the degree of expansion of the swirling fluid being transported, allowing the jet width of the dual jets in the straight-line direction to be expanded. As a result, the transported fluid can be efficiently spread and delivered to the entire range set as the target position T, and the functions of the transported fluid can be effectively utilized throughout the entire range of the target position T.

[0040] In the fluid transport device according to the above embodiment, the first fluid supply unit 30 is configured to have only one supply pipe 31 and blower 32 for supplying the fluid to be transported to the inner nozzle 21. However, the device is not limited to this configuration, and it is also possible to have multiple supply pipes and blowers configured.

[0041] For example, the internal nozzle 21 can be configured with a supply pipe for introducing the fluid to be conveyed, consisting of a first supply pipe that introduces the fluid in the axial direction of the internal nozzle 21 to create a straight component of the swirling flow, and a second supply pipe that introduces the fluid in the tangential direction of the circular cross-section of the internal nozzle 21 to create a swirling component of the swirling flow, and each of these supply pipes can be provided with a blower to supply the fluid to be conveyed.

[0042] Furthermore, in the fluid conveying device according to the above embodiment, the fluid to be conveyed and the second fluid are supplied directly to each nozzle 21, 22 from the blowers of the first fluid supply unit 30 and the second fluid supply unit 40, and no special measures are taken to address disturbances that may occur in each fluid. However, the device is not limited to this configuration, and it is also possible to provide means for suppressing disturbances to the fluid to be conveyed and the second fluid.

[0043] For example, as a means of suppressing disturbances, a stagnation chamber that attenuates the disturbance component of the conveyed fluid leaving the blower may be provided in the fluid path between the blower and the inner nozzle, or a stagnation chamber that attenuates the disturbance component of the second fluid leaving the blower may be provided in the fluid path between the blower and the outer nozzle. Furthermore, as another means of suppressing disturbances, a flow-straightening grid such as a honeycomb can be provided upstream of the nozzle or inside the nozzle.

[0044] Furthermore, in the fluid conveying device according to the above embodiment, the conveyed fluid and the second fluid are configured to be ejected from a gas based on indoor air or from indoor air itself, so that both have substantially similar physical properties as fluids. However, the device is not limited to this, and the conveyed fluid can be configured to be ejected from a fluid with different fluid properties from the second fluid, thereby giving a special flow state to the swirling flow of the conveyed fluid.

[0045] For example, when using only a gas such as air as the second fluid, the transported fluid may be made denser than the second fluid, for example, by containing a mist of a liquid having a predetermined function within the gas. In this case, the transported fluid can reach a greater distance because it is less likely to diffuse due to the density difference with respect to the second fluid. Furthermore, if the system is set to evaporate the mist along the way, it will change into a flowing state as a gas, allowing it to reach the target position with sufficient spread and effectively utilize the functions of the transported fluid.

[0046] Furthermore, in the fluid conveying device according to the above embodiment, the position of the nozzle with respect to the flow direction is set to be the same for the first nozzle 11 and the second nozzle 12, but the device is not limited to this, and the position difference between the two nozzles may be within a range corresponding to the diameter of the first nozzle. Even if there is a position difference between the nozzles, as long as it remains within the above range, the annular jet ejected from the second nozzle will function as an air curtain, similar to the above embodiment, and the diffusion of the swirling flow of the conveyed fluid ejected from the first nozzle can be suppressed.

[0047] Furthermore, in the fluid transport device according to the above embodiment, the tip shape of the nozzles 21 and 22, where the outlets 11 and 12 are located, is formed in a tapered nozzle shape. However, the device is not limited to this, and other shapes, such as a simple cylindrical shape, can also be used. [Examples]

[0048] In an experiment in which a dual jet combining a swirling flow and an annular jet is ejected using the fluid conveying device disclosed in the present invention, the diffusion state and spread width of the conveyed fluid forming the swirling flow were measured, and the performance of the device was evaluated and verified.

[0049] (Example 1) First, as Embodiment 1 of the fluid conveying device disclosed in the present invention, an experiment was conducted to evaluate the characteristics of a dual jet, which combines a swirling flow and an annular jet, by ejecting it from the fluid conveying device under conditions where it is less susceptible to disturbances inside and outside the device.

[0050] As shown in Figure 4, the experiment involved a dual jet, consisting of a swirling flow of the transported fluid and an annular jet of a second fluid, ejected from a dual nozzle of a fluid transport device located in a wind tunnel WT, which is designed to avoid the influence of disturbances in the surrounding environment. The jet was visualized using smoke, photographed with a high-speed camera (HSC), and the flow velocity was measured using a laser Doppler flowmeter (LDV). The wind tunnel WT, which ejects the fluid to be transported and a second fluid from within, has dimensions of 2500 x 2000 x 1600 mm (length x width x height) and is a known device with a structure that prevents external disturbances from being transmitted to the internal space.

[0051] The high-speed camera (HSC) captures images at a speed of 1000fps. A computer connected to this camera receives the captured image data, enabling it to obtain instantaneous images for each frame and time-averaged images by averaging multiple instantaneous images. For fluid visualization during capture, a laser sheet light is emitted from a laser light source (LS). The thickness of this sheet light is set to 1 mm.

[0052] Furthermore, for visualization during filming and velocity measurement using a flow meter, a known tracer generation device (not shown in the diagram) is provided in the flow paths of the transported fluid and the second fluid, and the generated particles (traceers) can be supplied to the transported fluid and the second fluid as needed. The particles (tracers) introduced using these tracer generation devices for flow visualization and velocity measurement with laser Doppler flowmeters are said to be oil mist with a size of 0.7 μm.

[0053] As shown in Figures 4 to 6, the fluid transport device used in the performance evaluation experiment comprises a double-cylinder double nozzle 20 having an inner nozzle 23 and an outer nozzle 24, a first fluid supply unit 35 that supplies the fluid to be transported to the inner nozzle 23, a second fluid supply unit 45 that supplies a second fluid to the outer nozzle 24, and stagnation chambers 51 and 52 as means for suppressing disturbances.

[0054] The dual nozzle 20 integrates an inner nozzle 23, whose circular opening at the tip is designated as the first nozzle 11, and an outer nozzle 24, whose annular opening region located on the outer circumference of the tip opening of the inner nozzle 23 is designated as the second nozzle 12, in a coaxial arrangement.

[0055] Inner diameter d of inner nozzle 23 c The diameter is 30mm, and the inner diameter of the outer nozzle 24 is d a The diameter is set to 65 mm, and the nozzle length, i.e., the length of the double cylinder forming the double nozzle, is set to 150 mm. In addition, in order to generate a swirling velocity component of the conveyed fluid in the inner nozzle 23, multiple swirling flow supply pipes 25 with a diameter of 8 mm are connected in the tangential direction to the cylindrical body forming the inner nozzle 23.

[0056] The first fluid supply unit 35 comprises a supply pipe 36 that introduces the fluid to be conveyed as the swirling component of the swirling flow through a swirling flow supply pipe 25 to the inner nozzle 23, a first blower 37 that sends a portion of the fluid to be conveyed that becomes the swirling component of the swirling flow toward the inner nozzle 23 through the supply pipe 36, and a second blower 38 that sends the other portion of the fluid to be conveyed that becomes the straight-traveling component of the swirling flow toward the inner nozzle 23 through a stagnation chamber 51. The fluid to be conveyed by each of the blowers 37 and 38 is indoor air.

[0057] The second fluid supply unit 45 is configured to include a second supply pipe 46 that introduces a second fluid into the outer nozzle 24 through a stagnation chamber 52, and a blower 47 that delivers indoor air as the second fluid through this supply pipe 46.

[0058] The stagnation chamber 51 is formed as a box-shaped structure having an internal space of a predetermined volume, connected to the outlet side of the second blower 38 of the first fluid supply unit 35. The internal space is also connected to the end of the internal nozzle 23, allowing the conveyed fluid that has exited the blower 38 to flow into the internal space, attenuate its disturbance components, and then direct it towards the internal nozzle 23.

[0059] The stagnation chamber 52 is formed as a box-shaped structure having an internal space of a predetermined volume, connected to the outlet side of the supply pipe 46 of the second fluid supply unit 45. The internal space is also connected to the annular space between the outer nozzle 24 and the inner nozzle 23, allowing the second fluid sent out by the blower 47 to flow into the internal space, attenuate its disturbance components, and then direct it towards the outer nozzle 24. The capacities of the stagnation chambers 51 and 52 are set according to the supply conditions of each fluid by the respective blowers 37, 38, and 47, so that the values ​​of the ejection velocities at each nozzle 11 and 12 satisfy the desired conditions.

[0060] A portion of the conveyed fluid, sent out from the first blower 37 of the first fluid supply unit 35, flows through the supply pipe 36 and the swirling flow supply pipe 25 along the inner circumference of the inner nozzle 23, generating a swirling component of the swirling flow. Meanwhile, the other portion of the conveyed fluid, sent out from the second blower 38, flows through the stagnation chamber 51 to the end of the inner nozzle 23, generating a straight component of the swirling flow. As a result, the swirling flow of the conveyed fluid, synthesized within the inner nozzle 23, is ejected from the first nozzle 11 at the tip of the inner nozzle 23.

[0061] In performance evaluation tests, the ejection velocity U, which is the straight-line velocity component in the swirling flow of the conveyed fluid, is measured. c And the ejection velocity U of the second fluid jet a The velocity ratio γ1 = U a / U c The value of can be any of four values: 0.25, 0.5, 0.75, or 1.0, and the ejection velocity U is the straight-line velocity component in the swirling flow of the conveyed fluid. c And other ejection velocities U, which are the swirling velocity components. s The velocity ratio γ2 = U s / U cThe experiment will be conducted under the condition that the value of takes one of four possible values: 0.25, 0.5, 1.0, or 1.5. U c , U a , U s The values ​​for each are shown in Table 1 below.

[0062] [Table 1]

[0063] The Reynolds number Re of the fluid being transported ejected from the first nozzle 11 is determined by the density ρ of the fluid being transported and the ejection velocity (cross-sectional mean velocity) U of the fluid being transported. c , diameter d of the first nozzle c Using the viscosity coefficient μ and the kinematic viscosity coefficient ν, Re=ρU c d c / μ=U c d c / ν This can be expressed as such, but in experiments, the value of the Reynolds number Re is treated as fixed at Re=3000.

[0064] As an experiment to evaluate the change in diffusion characteristics due to differences in velocity conditions of a double jet, first, the ejection velocity U of the transported fluid c and the ejection velocity U of the second fluid a The velocity ratio γ1 = U a / U c For each of the values ​​of 0.25, 0.5, 0.75, and 1.0, the conveyed fluid ejected from the tip of the double nozzle 20 was visualized and photographed using a high-speed camera. In this photography, the ejection velocity U, which is the straight-line velocity component in the swirling flow of the conveyed fluid, was observed. c And other ejection velocities U, which are the swirling velocity components. s The velocity ratio γ2 = U s / U c The value of was fixed at 0.5 for the experiment. The visualized photographic images (instantaneous images) obtained by the shooting are shown in Figures 7 to 10.

[0065] Next, the ejection velocity U is the straight-line velocity component in the swirling flow of the conveyed fluid. cAnd other ejection velocities U, which are the swirling velocity components. s The velocity ratio γ2 = U s / U c For each of the values ​​of 0.25, 0.5, 1.0, and 1.5, the conveyed fluid ejected from the tip of the double nozzle 20 was visualized and photographed with a high-speed camera. In this photography, the ejection velocity U of the conveyed fluid was observed. c and the ejection velocity U of the second fluid a The velocity ratio γ1 = U a / U c The value was fixed at 0.75 for the experiment. The visualized photographic images (instantaneous images) obtained by the shooting are shown in Figures 11 to 14.

[0066] As a comparative example, consider the case where the fluid to be transported is ejected without swirling, i.e., the velocity ratio γ2 = U s / U c We also took photos in the case where =0. In this case, the velocity ratio γ1 = U a / U c The value of is set to 0.5. The visualized photographic image (instantaneous image) obtained from this shooting is shown in Figure 15.

[0067] From the differences between the four examples with varying speed ratios γ1 shown in Figures 7 to 10 and the comparative example shown in Figure 15, the following can be observed. 1. The flow of a swirling flow is significantly different from that of a circular jet without swirling motion. 2. When a swirling speed is applied, tiny vortices are generated around the swirling flow. 3. When the velocity of the annular jet is low, the swirling flow tends to spread easily. Conversely, when the velocity of the annular jet is high, the swirling flow does not spread easily but tends to meander.

[0068] Furthermore, the following can be seen from the differences between the four examples with varying velocity ratios γ2 shown in Figures 11 to 14 and the comparative example shown in Figure 15. 4. When the turning speed is low, the swirling flow does not spread easily, and conversely, when the turning speed is high, the swirling flow spreads easily. 5. The width and diffusion characteristics of the swirling flow can be changed by the swirling speed. In other words, the swirling speed can be a control parameter for the width and diffusion state of the swirling flow.

[0069] Next, as a second experiment to evaluate the change in diffusion characteristics due to differences in the velocity conditions of the double jet, the ejection velocity U of the transported fluid was used. c and the ejection velocity U of the second fluid a The velocity ratio γ1 = U a / U c When the value of is 0.25, 0.5, 0.75, and 1.0, the ejection velocity U is the straight-line velocity component in the swirling flow of the conveyed fluid, respectively. c And other ejection velocities U, which are the swirling velocity components. s The velocity ratio γ2 = U s / U c For each of the 16 conditions, in which the value of was changed to four different values ​​(0.25, 0.5, 1.0, and 1.5), both the transported fluid forming the double jet and the second fluid were visualized, and images were captured using a high-speed camera. Multiple frames of instantaneous images were averaged to obtain a time-averaged image. In addition, the length L at the tip of the potential core of the swirling flow was measured for each of the above conditions. p and the maximum width W of the potential core region p Measurements were taken, and the relationship between the speed ratio and these measured values ​​was plotted on graphs.

[0070] Figures 16 to 19 each show four examples of visualization photographs (time-averaged images) of the double jet ejected from the tip of the double nozzle 20. Figure 20 shows the length L of the potential core tip, measured for each of the velocity ratio conditions γ1 and γ2. p Nozzle diameter d c Ratio L p / d c The graph shown is obtained by plotting the values ​​of [the variable]. Figure 21 shows the maximum width W of the potential core region measured for each of the ejection velocity ratio conditions γ1 and γ2. p Nozzle diameter d c Ratio W p / d c The graph shown is obtained by plotting the values ​​of [the variable].

[0071] In any of the graphs, the length L of the potential core tip p , and the maximum width W of the potential core region p are divided by the diameter d of the first ejection port 11 at the tip of the inner nozzle 21 c to represent them as values of dimensionless ratios that do not change according to the size of the diameter d of the ejection port 11 c .

[0072] From the photographic images of FIGS. 16 to 19 and the graphs of FIGS. 20 and 21, the following can be understood 1. The greater the swirling speed, the shorter the potential core length and the greater the jet width tend to be 2. The potential core length is maximum under the condition that the speed ratio γ1 of the jet speed of the swirling flow and the jet speed of the annular jet is 0.75[[ID=​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​ / U c The relationship between the distance Z and the values ​​is shown in the graphs in Figure 22.

[0074] Figure 22 shows the flow direction velocity U at a predetermined position on the nozzle's central axis. z The ejection velocity U of the fluid being transported c Velocity ratio U z / U c And the nozzle diameter d at the distance Z to the predetermined position. c The ratio Z / d c This graph shows the relationship between [the two factors]. In the graph, distance Z is the diameter d of the first nozzle 11 at the tip of the inner nozzle 23. c By dividing by this, the diameter d of the nozzle 11 is obtained. c It is expressed as a dimensionless ratio value that does not change according to the magnitude of the two factors.

[0075] Graph in Figure 22 (U on the nozzle central axis) z From the velocity distribution, the following can be understood: 1. As the velocity ratios γ1 and γ2 change, the jet velocity along the nozzle's central axis also changes. 2. Under the conditions of γ1=0.75 and γ2=0.25, where the transport effect is high, the velocity near the tip of the potential core is the nozzle velocity U c This represents 82%. 3. Based on the above 2, the jet velocity U at the first nozzle 11 is determined based on the velocity U at the tip of the potential core. c If you want to set it, U c It can be said that setting it to =U / 0.82 is sufficient.

[0076] (Example 2) Furthermore, as an embodiment 2 of the fluid transport device disclosed in the present invention, an experiment was conducted to evaluate the resistance of the double jet characteristics to disturbances in an environment with disturbances, using a device that does not have means to suppress disturbances.

[0077] As shown in Figure 23, the fluid transport device used in the experiment to evaluate resistance to this disturbance has a double nozzle 26 made of a double cylinder having an inner nozzle 27 and an outer nozzle 28, a first fluid supply unit 60 that supplies the fluid to be transported to the inner nozzle 27, and a second fluid supply unit 70 that supplies a second fluid to the outer nozzle 28.

[0078] The dual nozzle 26 integrates an inner nozzle 27, whose circular opening at the tip is designated as the first nozzle 11, and an outer nozzle 28, whose annular opening region located on the outer circumference of the tip opening of the inner nozzle 27 is designated as the second nozzle 12, in a coaxial arrangement. However, the inner diameter d of the inner nozzle 27 c The diameter is 25mm, and the inner diameter of the outer nozzle 28 is d a The diameter is set at 50 mm, and the nozzle length, that is, the length of the double cylinder forming the double nozzle, is set at 300 mm.

[0079] The first fluid supply unit 60 is configured to include a supply pipe 61 that is connected to the inner nozzle 27 so that the fluid to be conveyed flows in in a direction having a swirling velocity component along the inner circumference of the inner nozzle 27 and a velocity component moving straight toward the first outlet 11, and a blower 62 that sends the fluid to be conveyed through the supply pipe 61. The second fluid supply unit 70 is configured to include a blower connected to the end of the outer nozzle 28 for supplying the second fluid.

[0080] Furthermore, in order to visualize the conveyed fluid and the second fluid, a known tracer generation device (not shown) is provided in the flow paths of the conveyed fluid and the second fluid, similar to the case of Example 1, and the generated particles (traceers) can be supplied to the conveyed fluid and the second fluid as needed.

[0081] The experiment begins with measuring the ejection velocity U of the fluid being transported. c and the ejection velocity U of the second fluid a The velocity ratio γ1 = U a / U c The value of is 0.75, and the ejection velocity U is the straight-line velocity component in the swirling flow of the conveyed fluid. c And other ejection velocities U, which are the swirling velocity components. sThe velocity ratio γ2 = U s / U c For a double jet with a value of 0.25, under conditions where disturbances are present, the visualized double jet was photographed with a high-speed camera (HSC), and the length L at the tip of the potential core of the swirling flow was also measured. p , maximum width W of the potential core region p Furthermore, the flow velocity at the tip of the potential core was measured.

[0082] As detailed experimental conditions, the jet velocity U of the straight-line velocity component in the swirling flow ejected from the inner nozzle was c The velocity is 2 m / s, the Reynolds number Re is 3300, and the annular jet velocity U ejected from the outer nozzle is 2 m / s. a The ejection velocity U is 1.5 m / s, which is the swirling velocity component in the swirling flow of the conveyed fluid. s Each is set to 0.5 m / s.

[0083] The measurement result is the length L of the tip of the potential core. p 290mm (11.6d c ), maximum width W of the potential core region p 40mm (1.6d c The flow velocity at the tip of the potential core was 1.64 m / s. Figure 23 shows a visualization photograph (time-averaged image) of the swirling flow ejected from the tip of the double nozzle 26 during measurement.

[0084] The following two points were confirmed from the measurement results. 1. The jet characteristics are almost the same as those obtained in the experiment when the above-mentioned disturbances are absent, and it can be concluded that the influence of disturbances within the device is small. 2. The jet velocity also matches the characteristic value confirmed in advance under conditions without disturbance, indicating a similarity.

[0085] In addition, the ejection velocity U is the straight-line velocity component in the swirling flow of the conveyed fluid. c And other ejection velocities U, which are the swirling velocity components. s The velocity ratio γ2 = U s / U cFor each of the values ​​of 0.25, 0.75, and 1.0, under the condition of disturbance, the length L at the tip of the potential core of the swirling flow p The following was obtained: Here, the ejection velocity U of the conveyed fluid. c and the ejection velocity U of the second fluid a The velocity ratio γ1 = U a / U c The value was fixed at 0.75.

[0086] Then, for the length of the potential core tip for each obtained velocity ratio γ2, the velocity ratio γ1 = U under the condition that no disturbance exists. a / U c The value of is 0.75, and γ2 = U s / U c The ratio (straightness) to the length of the tip of the potential core was calculated when the value of was 0.25.

[0087] As a comparative example, consider the case where the fluid to be transported is ejected without swirling, i.e., the velocity ratio γ2 = U s / U c Similarly, for the case where =0, the length L at the tip of the potential core is the same. p We obtained the data and calculated the ratio (straightness ratio) to the length of the potential core tip under the condition that no disturbances exist.

[0088] Figure 24 is a graph showing the relationship between the velocity ratio γ2 of the ejection velocity and the straightness ratio. As shown in Figure 24, three examples and a comparative example with varying velocity ratios γ2 indicate that the straight-line accuracy of the double jet is improved by ejecting the transported fluid as a swirling flow. In particular, the highest straight-line accuracy (90% of the case without disturbance) is achieved at a velocity ratio γ2 = 0.75. This is approximately 1.5 times the straight-line accuracy in the case without swirling.

[0089] From the experimental results described above, in the fluid conveying device disclosed in the present invention, the annular jet ejected from the second nozzle 12 in the double jet system functions as an air curtain, suppressing the diffusion of the conveyed fluid ejected as a swirling flow from the first nozzle 11. This diffusion state of the conveyed fluid changes the ejection velocity of the annular jet (velocity ratio γ1 = Ua / U c (Changing the value of) and changing the swirling speed of the swirling flow (speed ratio γ2 = U s / U c It can be controlled by either of the following methods (changing the value of ).

[0090] In particular, the conditions γ1=0.75 and γ2=0.25 allow for the maximum length of the potential core that can transport the fluid while suppressing diffusion and keeping it within the annular jet, resulting in the highest velocity ratio for efficient fluid transport. Furthermore, beyond the tip of the potential core, the diffusion suppression effect of the double jet weakens, allowing for increased diffusion of the fluid to be transported, thus enabling the fluid to spread to the desired width at the target position.

[0091] Furthermore, the diffusion characteristics of these dual jets are roughly the same even under conditions close to real-world conditions that take disturbances into account, and it can be said that adding a swirl significantly improves resistance to disturbances compared to the case without a swirl.

[0092] From the above, it is clear that the fluid conveying device disclosed in the present invention can efficiently convey the fluid to be conveyed while suppressing its diffusion by using a double jet with added swirling flow, can flexibly control the spread width of the fluid to be conveyed at the target position, and minimizes the influence of disturbances inside and outside the device on its characteristics. [Explanation of Symbols]

[0093] 1. Fluid conveying device 11 First vent 12 Second vent 20 Dual Nozzles 21, 23 Inner nozzle 22, 24 Outer nozzles 25 Swirling flow supply pipe 26 Dual Nozzle 27 Inner nozzle 28 Outer nozzle 30, 35 First fluid supply section 31, 36 Supply pipe 32 Blower 33 Air purification device 37, 38 Blower 40, 45 Second fluid supply section 41, 46 Supply pipe 42, 47 Blower 51, 52 Stagnation Room 60 First fluid supply section 61 Supply pipe 62 Blower 70 Second fluid supply section

Claims

1. A first nozzle is provided on the front side of the circular opening from which the fluid to be conveyed can be ejected, It comprises a second nozzle, which is arranged as an annular opening surrounding the outside of the first nozzle and capable of ejecting a predetermined second fluid, The first nozzle ejects the fluid to be conveyed as a swirling flow that moves toward the front of the opening while rotating around a virtual central axis extending toward the front of the opening. The second nozzle ejects the second fluid as an annular jet surrounding the fluid to be conveyed, towards the front of the opening. A fluid transport device with distinctive features.

2. In the fluid conveying apparatus described in claim 1, The ejection velocity U is the velocity component of the swirling flow of the conveyed fluid that travels in a straight line toward the opening front side at the first nozzle. c And the ejection velocity U at the second nozzle of the second fluid jet. a Toga, 0.25≦U a / U c ≦1 It is set to satisfy the following conditions A fluid transport device with distinctive features.

3. In the fluid conveying apparatus described in claim 1, One ejection velocity U is the velocity component of the swirling flow of the conveyed fluid that travels in a straight line toward the opening front side of the first nozzle. c And, the other ejection velocity U, which is the swirling velocity component at the first nozzle. s Toga, 0<U s / U c ≦1.5 It is set to satisfy the following conditions A fluid transport device with distinctive features.

4. In the fluid conveying apparatus described in claim 1, The second nozzle is provided such that the radial width of the annular opening is less than or equal to the diameter of the first nozzle. A fluid transport device with distinctive features.

5. In the fluid conveying device according to any one of claims 1 to 4, An inner nozzle with a circular opening at its tip which serves as the first nozzle, An outer nozzle is arranged to surround the outer circumference of the inner nozzle, and the annular opening region located on the outer circumference side of the tip opening of the inner nozzle at the tip opening is designated as the second nozzle, A first fluid supply unit that supplies the fluid to be conveyed to the internal nozzle, The system includes a second fluid supply unit that supplies the second fluid to the outer nozzle. A fluid transport device with distinctive features.

6. In the fluid conveying apparatus described in claim 5, A disturbance suppression means is provided on the upstream side of at least one of the first and second nozzles. A fluid transport device with distinctive features.

7. The fluid to be conveyed is ejected from the first nozzle, which is arranged as a circular opening, towards the front of the opening, A predetermined second fluid is ejected from a second nozzle, which is arranged as an annular opening surrounding the outside of the first nozzle. The conveyed fluid is ejected as a swirling flow that moves toward the front of the opening while swirling around a virtual central axis extending toward the front of the opening of the first nozzle. The second fluid is ejected as an annular jet surrounding the fluid to be conveyed, on the front side of the opening of the second nozzle. A fluid transport method that is characterized by its features.

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