JP2011240269A - Atomizing mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an atomizing mechanism in which the atomizing effect of liquid droplets is drastically improved and the atomization thereof is sufficiently achieved even when generating the liquid droplets in concentrated amount.SOLUTION: A collision member 22 is provided to protrude from the inner face of a flow path wall part 25, and a gap-forming part 23 is provided to face a top of the collision member 22 in a protruding direction in a flow path FP. A bypass 251 is formed between the outer peripheral face of the collision member 22 and the inner face of the flow path wall part 25, and a squeezing gap 21G for allowing passage of flow while squeezing is formed so as to become lower in flow volume and higher in flow rate than the bypass 251 between the collision member 22 and the gap-forming part 23. A suction hole 226 is formed in the collision member 22 in such a form as to penetrate the collision member 22 as well as the flow path wall part 25. The suction hole has, at one end being the tip end of the member 22, and an opening as a liquid jetting port in the squeezing gap 21G, and has an opening as a liquid intake port on the outer face of the wall part at the other end penetrating the flow path wall part 25.

Description

  The present invention relates to a spray mechanism.

  There are various methods for atomizing a liquid, and as one of them, a method is known in which a gas and a liquid are mixed and supplied to an atomizing nozzle having a constricted portion and ejected as a mist from the nozzle tip. (For example, Patent Documents 1 and 2).

JP 2004-16846 A JP 2006-175358 A

  However, the conventional atomizing nozzle has a drawback that the passage resistance of the aperture hole is large and it is difficult to obtain fine droplets.

  It is an object of the present invention to provide a spray mechanism that can sufficiently achieve the miniaturization even when the droplet miniaturization effect is dramatically improved and a high-concentration droplet is generated.

Means for Solving the Problems and Effects of the Invention

In order to solve the above problems, the first configuration of the spray mechanism of the present invention is:
A hollow flow path forming member having a fluid inlet and a spray outlet for introducing a gas or gas-liquid mixed fluid and having a flow path from the fluid inlet toward the spray outlet formed therein;
A collision member protruding from the inner surface of the flow path wall of the flow path forming member;
Having a gap forming portion facing the leading end of the collision member in the flow path in the flow path;
A detour channel portion is formed between the outer peripheral surface of the collision member and the inner surface of the channel wall portion, and a lower flow rate and a higher flow velocity are provided between the collision member and the throttle gap forming portion than the detour channel portion. A throttle gap that allows the gas-liquid mixed flow to pass while being throttled is formed,
The collision member has a flow passage wall portion and a projection wall that penetrates the collision member in the projecting direction. One end side opens a liquid outlet in the throttle gap at the front end side of the collision member, and the other end side is the flow path wall. A suction hole is formed in the outer surface of the wall portion to open the liquid intake through the portion,
Liquid is sucked into the narrowing gap from the liquid inlet through the suction hole by the negative fluid pressure generated in the throttling gap to form liquid droplets, collides with the collision member, passes through the detour channel section, and the collision member It is characterized in that the droplets are pulverized by being involved in the wrapping turbulent flow that wraps around the downstream side and sprayed from the spray outlet.

Further, the second configuration of the spray mechanism of the present invention has a fluid inlet and a spray outlet for introducing a gas-liquid mixed fluid, and a hollow passage formed inside from the fluid inlet to the spray outlet. A flow path forming member;
A collision member protruding from the inner surface of the flow path wall of the flow path forming member;
Having a gap forming portion facing the leading end of the collision member in the flow path in the flow path;
A detour channel portion is formed between the outer peripheral surface of the collision member and the inner surface of the channel wall portion, and a lower flow rate and a higher flow velocity are provided between the collision member and the throttle gap forming portion than the detour channel portion. A throttle gap that allows the gas-liquid mixed flow to pass while being throttled is formed so that the droplets contained in the gas-liquid mixed fluid that passes through the throttle gap collide with the collision member and pass through the detour flow path section. It is characterized in that it is pulverized by being entrained in a wraparound turbulent flow that circulates downstream and sprayed from the spray outlet.

  According to the first configuration of the present invention, the collision member is provided so as to protrude from the inner surface of the flow path wall portion of the flow path forming member, and is opposed to the front end in the protrusion direction of the collision member in the flow path. A gap forming part is provided. A bypass flow path is formed between the outer peripheral surface of the collision member and the inner surface of the flow path wall, and a lower flow rate and a higher flow rate than the bypass flow path between the collision member and the throttle gap forming section. A throttling gap is formed to allow the flow to pass while throttling so as to achieve a flow velocity. When a flow composed of a gas or a gas-liquid mixed fluid is supplied to the spray mechanism having such a structure, the flow is throttled by the throttle gap and the flow velocity is increased. As a result, negative pressure is generated in the throttle gap, and liquid is sucked and supplied to the throttle gap through the suction hole of the collision member communicating with the throttle gap. The sucked liquid is supplied from the fluid inlet, is entrapped in a high-speed throttle gap flow, and is pulverized to form droplets.

  In the second configuration of the present invention, the suction hole is not formed in the collision member, and the gas-liquid mixed fluid is supplied to the throttle gap from the fluid inlet. The rest is the same as in the first configuration, and the droplets contained in the gas-liquid mixed fluid are pulverized by being caught in a high-speed throttle gap flow.

  In both the first and second configurations, a part of the flow supplied from the fluid inlet collides with the collision member forming the throttle gap, but the collision member and the flow path wall forming the throttle gap A detour channel section that detours the flow that collides with the collision member is formed between the two sections. As a result, the resistance of the fluid passing through the throttle gap does not increase excessively, and as a result, a much faster flow passes through the throttle gap and the pulverization of the droplets contained in the flow proceeds. It becomes easy. In addition, since the passage flow velocity of the throttle gap is increased, a large number of minute vortices are formed over the entire three-dimensional negative pressure region that is formed in a three-dimensional wide-angle area on the downstream side. Further, separately from this, the flow that collides with the collision member and passes through the detour channel portion flows around the downstream side of the collision member, and a violent turbulent flow with a larger flow rate is superimposed on the negative pressure region. The flow through the constriction gap containing the droplets is vigorously and randomly stirred three-dimensionally by these two turbulences, and as a result of the large number of micro vortices surrounding the droplets trying to draw the droplets into themselves, The fine pulverization of the droplets proceeds efficiently, and droplets having a high concentration and a small particle diameter can be easily obtained.

For example, when a collision member having a cylindrical cross section is arranged in the flow, the Reynolds number Re is given by assuming that the outer diameter of the collision member is D, the flow velocity is U, and the kinematic viscosity coefficient of water is ν.
Re = UD / ν (Dimensionless number) (1)
It is known that the flow around the collision member having a cylindrical cross section is turbulent when the Reynolds number Re is 1500 or more. The crushing effect is greatly improved.

Hereinafter, various requirements that can be added to the configuration of the spray mechanism of the present invention will be described.
First, the detour channel portion can be formed only on one side of the collision member in the flow direction when viewed from the flow direction, but the detour channel section is detoured on both sides of the collision member as viewed from the flow direction. If the flow path is formed, the turbulent flow wraps around from both sides of the collision member toward the negative pressure area downstream of the narrowing gap, so that the droplet crushing effect is further enhanced and fine droplets are more efficiently Can be generated.

  Between the fluid inlet and the spray mechanism, a preparation throttle mechanism that accelerates the flow from the fluid inlet and guides it to the spray mechanism can be provided. By providing such a preparation throttle mechanism, it is possible to further increase the flow velocity in the throttle gap and its surroundings, and to measure further miniaturization and higher concentration of the droplets.

  Next, a decompression cavity can be formed in at least one of the opposing surfaces that form the aperture gap between the collision member and the gap forming portion. If the decompression cavity is resonated in the flow, an ultrasonic band resonance wave is generated by the resonance, and the droplet crushing can be further promoted by the resonance vibration.

  Next, at least one of the opposing surfaces forming the aperture gap of the collision member and the gap forming portion is formed as an aperture inclined surface that gradually reduces the interval of the aperture gap from the upstream side to the downstream side on the inflow side. can do. As a result, the opposing gap of the throttle gap decreases continuously as it goes from the throttle gap inlet to the back of the gap, so that the flow can be smoothly throttled toward the back of the gap, reducing the flow loss when passing through the gap and reducing the flow velocity. Can be increased. Further, at least one of the opposing surfaces forming the aperture gap of the collision member and the gap forming portion is formed as an enlarged inclined surface that gradually expands the interval of the aperture gap from the upstream side toward the downstream side on the outflow side. You can also.

  If the gap of the throttle gap is reduced in the spray mechanism of the present invention, the flow rate through the gap decreases while the flow rate in the bypass channel increases. Therefore, if the aperture gap interval is reduced within a range where the flow velocity of the aperture gap does not decrease excessively, the effect of miniaturization due to the turbulent flow of micro droplets generated in the aperture gap is enhanced, and droplets with a smaller diameter are Can occur. On the other hand, if the gap between the narrowing gaps is increased, the flow resistance in the narrowing gap is reduced, so that the flow rate of the injection can be increased over the entire cross-section of the bypass channel (in this case, the gap interval is set). Depending on the value, the flow velocity in the throttle gap may tend to be slightly insufficient, but it is advantageous when priority is given to securing the injection flow rate). Therefore, if the spray gap mechanism of the present invention is provided with a throttle gap interval adjustment mechanism that adjusts the gap of the throttle gap so that it can be changed, the aperture gap interval can be set according to the required level of droplet diameter reduction and jet flow rate. It can be adjusted as appropriate.

  Next, the gap forming portion can be formed as an opposing collision member that protrudes from the inner surface of the wall portion toward the collision member on the side opposite to the collision member with respect to the cross-sectional center of the flow path. It can form between a front-end | tip part and the protrusion direction front-end | tip part of an opposing collision member. For example, the narrowing gap may be formed by making the front end surface of the collision member face the inner peripheral surface of the flow channel wall. In this case, the portion of the flow channel wall facing the collision member constitutes the gap forming portion. Become. However, in this configuration, since the throttle gap is located in the outer peripheral region of the cross section of the flow path shaft where the flow loss due to wall friction is large, the flow velocity through the throttle gap tends to be small. However, by providing the opposing collision member, the formation position of the narrowing gap can be brought closer to the center of the cross section where the flow velocity is large, and the passage flow velocity of the narrowing gap increases, so that fine droplets can be generated more efficiently. .

In addition, a reduced diameter portion having a tapered peripheral side surface that decreases in diameter toward the distal end can be formed at a distal end portion facing at least one throttle gap between the collision member and the opposing collision member. By providing such a reduced diameter portion, the following effects are achieved.
-In the vicinity of the outer peripheral surface tip of the reduced diameter portion of the collision member or the opposing collision member, the flow detour length of the flow is shorter than the vicinity of the outer peripheral surface proximal end, and the flow velocity increases. Further, the portion located on the upstream side in the flow direction of the outer peripheral surface of the reduced diameter portion forms the above-described throttle inclined surface. As a result, the effect of generating turbulent flow in the vicinity of the narrowing gap is further enhanced, and the generation efficiency of fine droplets is further improved.
・ For the impact member and the opposing impact member, the effect of generating vortex or turbulent flow due to the detour of the flow is not only in the plane perpendicular to the opposing direction but also in parallel to the opposing direction (that is, the diameter is reduced). This also occurs in the direction over the constriction gap side), and the three-dimensional droplet pulverization effect is further enhanced.

  In the case where the opposing collision member is provided, the above-described decompression cavity that retracts in the gap forming direction can be formed on one or both of the collision member and the opposing collision member at the tip surface facing the throttle gap. In particular, if a configuration in which a reduced pressure cavity is formed in one of the collision member and the opposing collision member and a reduced diameter portion is formed on the other side in such a positional relationship that the tip thereof faces the opening of the reduced pressure cavity, the flow in the throttle gap is The speed can be greatly increased by the reduced diameter portion. The increased flow is brought into contact with the stagnation portion in the decompression cavity, resulting in a very large flow velocity difference. In addition, when the diameter of the reduced diameter portion is overcome, the flow is diverted to the reduced pressure cavity side in a bent form, so that the section length in which the flow velocity difference occurs is also increased (this effect is caused by a portion of the reduced diameter portion on the tip side being the reduced pressure cavity) This is more noticeable when the position is adjusted so as to enter the interior of the head). Furthermore, as will be described later, there is a possibility that the resonance effect of the decompression cavity can be made more conspicuous by forming this reduced diameter portion. Both contribute effectively to further miniaturization of droplets.

  Specifically, the narrowing gap has a wedge-shaped cross section when a peripheral region forming an opening peripheral portion of the decompression cavity and a tapered peripheral side surface of the reduced diameter portion are opposed to each other at the front end surface of the collision member, and An annular gap peripheral space whose outer peripheral side opens to the detour channel portion and a decompression cavity are formed via an annular constriction gap portion formed at a position opposed to the inner peripheral edge of the opening of the decompression cavity and the peripheral side surface of the reduced diameter portion. Therefore, it can be configured to communicate with each other. Thereby, the portions located on both sides of the narrowing gap in the flow direction of the outer peripheral surface of the reduced diameter portion also function as auxiliary gaps, and the flow velocity is improved, thereby contributing to the improvement in the generation efficiency of fine droplets.

  In addition, when providing an opposing collision member, it is good to form a detour channel part in the form spanning the outer peripheral surface of a collision member and the outer peripheral surface of an opposing collision member. As a result, both the collision member and the counter collision member wrap around and contribute to the generation of turbulent flow, and the effect of finely pulverizing the deposited droplets is further improved.

The block diagram which shows schematic structure of the fog generator using the spray mechanism of this invention. The top view and cross-sectional view of the spray nozzle which embodyed the 1st structure of the spray mechanism of this invention. The expanded-axis sectional view of the aperture gap structure formed using a collision member. The cross-sectional view which expands and shows the principal part of the spray nozzle of FIG. Explanatory drawing which shows typically the turbulent flow formation effect | action by a collision member. The figure explaining the concept by which a droplet is torn and micronized by a some eddy current. The axial sectional view showing the 1st modification of an aperture gap. The axial sectional view which shows the 2nd modification similarly. The axial sectional view which shows a 3rd modification similarly. The axial sectional view which shows the 4th modification similarly. The axial sectional view which shows the 5th modification similarly. Similarly, an axial sectional view showing a sixth modification. Similarly, an axial sectional view and a transverse sectional view showing a seventh modification. Similarly, an axial sectional view and a transverse sectional view showing an eighth modification. The cross-sectional view which expands and shows the principal part of the spray nozzle which embodied 2nd structure of the spray mechanism of this invention. The block diagram which shows schematic structure of the fog generating apparatus which used together the spray nozzle which embodied the 1st structure of the spray mechanism of this invention, and the spray nozzle which implemented the 2nd structure.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a block diagram showing a schematic configuration of a fog generating apparatus using the spray mechanism of the present invention. The main part of the apparatus is a spray nozzle 21 having the first requirement of the spray mechanism of the present invention, and an air flow supply pipe 304 is connected to a fluid inlet 31 (described later), while formed on the collision member 22. The liquid supply pipe 305 is connected to a suction hole (described later). A compressor 300 is connected to the airflow supply pipe 304, and pressurized gas is supplied while the pressure is adjusted by the valve 303, while a liquid to be sprayed is supplied from the liquid tank 301 to the liquid supply pipe 305, and sprayed. While being mixed with gas in the nozzle 21, it becomes droplets and is sprayed as mist MST from the spray outlet 106.

  The gas is, for example, air, but is not particularly limited thereto, and diluted with oxygen, carbon dioxide, nitrogen, inert gas (argon, helium, etc.), hydrogen, ozone (air, oxygen, carbon dioxide, inert gas, etc.) Various gases can be employed. Further, the liquid is, for example, water, but is not particularly limited thereto, and in addition to alcohol, gasoline, fossil fuel (light oil, heavy oil, etc.) may be employed.

  FIG. 2 shows an example of the structure of the spray nozzle 21. 3 and 4 are cross-sectional views showing an enlarged main part thereof. The spray nozzle 21 includes a flow path forming member 20 having a fluid inlet 31 and a spray outlet 106, a collision member 22 disposed inside the flow path forming member 20 in a radial direction from the flow path wall 25, and a flow path In the FP, there is a diaphragm gap forming portion 23 facing the front end portion of the collision member 22 in the protruding direction. The channel wall 25 is made of metal, ceramic or resin. As shown in FIG. 3, a detour channel portion 251 is formed between the outer peripheral surface of the collision member 22 and the inner surface of the channel wall portion 25 in the spray nozzle 21. In addition, a constriction gap 21G is formed between the collision member 22 and the constriction gap forming portion 23 to allow the flow to flow while constricting the flow so as to have a lower flow rate and a higher flow velocity than the bypass flow path portion 251.

  Further, a suction hole 226 is formed in the collision member 22. The suction hole 226 penetrates the collision member 22 together with the flow path wall portion 25 in the protruding direction into the flow path, and one end side of the suction hole 226 is located at the distal end side of the collision member 22 in the throttle gap 21G. 226d is opened, and the other end side is formed so as to pass through the flow path wall portion 25 and open a liquid inlet 226e on the outer surface of the wall portion (a tool engagement hole 226e and a decompression cavity 221 to be described later are suction holes). Part of it).

  As shown in FIGS. 4 and 5, the narrowing gap forming portion 23 is an opposing collision member (hereinafter referred to as “projecting”) that projects from the inner surface of the wall portion toward the collision member 22 on the side opposite to the collision member 22 with respect to the cross-sectional center O of the flow path FP. The constriction gap 21G is formed between the front end of the collision member 22 in the protruding direction and the front end of the opposing collision member 23 in the protruding direction.

  As shown in FIG. 2, a connecting male screw portion 274 is formed as a flow path connecting portion on the outer peripheral surface of the upstream end portion of the flow path forming member 20, and an O-ring 273 is fitted on the outer periphery of the base end portion 272. Has been. The flow path forming member 20 is connected to the air flow supply pipe 304 (FIG. 1) by screwing at the connecting male screw portion 274. Note that the flow path connecting portion is not limited to the threaded portion, and other known pipe connecting structures such as a one-touch joint may be adopted as long as the necessary pressure resistance can be secured.

  The flow path forming member 20 is formed with a preliminary throttle mechanism 30 between the fluid inlet 31 and the throttle gap 21G to accelerate the flow from the fluid inlet 31 and guide it to the throttle gap 21G. Specifically, the preparation throttle mechanism 30 includes a cylindrical introduction portion 31A that forms a fluid inlet 31, a reduced diameter portion 32 that is tapered toward the downstream side of the introduction portion 31A, and the reduced diameter portion 32. And a cylindrical small-diameter portion 30 </ b> S integrated in communication with the downstream side. Further, a preparatory enlarged portion 30A having a larger diameter than the small diameter portion 30S is formed in a cylindrical surface on the narrowing gap 21G side following the small diameter portion 30S. Further, the spray outlet 106 opened to the downstream side of the narrowing gap 21G is formed so as to expand in a tapered shape.

  Each of the collision member 22 and the counter collision member 23 is configured as a screw member made of metal (for example, stainless steel: for example, SUS316), and the front end side protrudes into the flow path FP with respect to the flow path wall portion 25, and the rear end side is It arrange | positions in the form which penetrates this flow-path wall part 25 so that it may be exposed to the outer peripheral surface of the flow-path wall part 25. FIG. A male threaded portion 22t is formed on the outer peripheral surface of the collision member 22, and is screwed into a female threaded hole 22u formed through the flow path wall 25. The interval of the aperture gap 21G can be adjusted according to the amount of screwing of the collision member 22 in the female screw hole 22u. A male threaded portion 23t is also formed on the outer peripheral surface of the opposing collision member 23, and is screwed into a female threaded hole 23u formed through the flow path wall 25. The interval of the throttle gap 21G can be adjusted according to the amount of screwing of the opposing collision member 23 in the female screw hole 23u. As described above, it is clear that the aperture gap interval adjusting mechanism that adjusts the interval of the aperture gap 21G so as to be changeable is realized. If both the collision member 22 and the opposing collision member 23 are screwed in the same direction, the position of the throttle gap 21G in the radial direction of the axial section of the flow path FP can be changed. In order to facilitate the adjustment of the screwing of these members, a tool mechanism that engages a tool such as a hexagon wrench with each head end surface of the collision member 22 and the opposing collision member 23 that protrudes outside the flow path wall portion 25. Joint holes 222 and 232 are respectively formed. When adjustment is not particularly performed with the interval or position of the aperture gap 21G being fixed, the collision member 22 and the opposing collision member 23 are fixed and integrated with the flow path wall 25 so as not to be screwed by insert molding or the like. It is also possible to configure. Furthermore, only one of the collision member 22 and the opposing collision member 23 can be screwed, and the other can be fixed and integrated with the flow path wall portion 25 so as not to be screwed.

  Next, as shown in FIG. 3, the collision member 22 is formed with a decompression cavity 221 that is retracted in the gap formation direction at the tip surface facing the throttle gap 21 </ b> G. Further, the opposing collision member 23 is formed with a reduced diameter portion 23k in such a positional relationship that the tip faces the opening of the decompression cavity 221 (however, the opposing collision member 23 is formed with a reduced pressure cavity and the collision member 22 has a reduced diameter. Part may be formed). The reduced diameter portion 23k formed on the opposing collision member 23 has a tapered peripheral side surface 231 (specifically, a conical surface) that decreases in diameter toward the tip. A portion located on the inflow side (flow upstream side) of the tapered peripheral side surface 231 forms a throttle inclined surface that gradually reduces the interval of the throttle gap 21G from the upstream side toward the downstream side. Further, the portion located on the outflow side (downstream side of the flow) constitutes an enlarged inclined surface that gradually expands the gap of the throttle gap 21G from the upstream side toward the downstream side.

  The collision member 22 and the opposing collision member 23 are disposed concentrically. The decompression cavity 221 has a cylindrical inner peripheral surface that is concentric with the outer peripheral surface of the collision member 22. The position of the reduced diameter portion 23k is adjusted in the axial direction so that a part of the distal end side enters the inside of the decompression cavity 221. As shown in FIG. 3, the narrowing gap 21G is formed by the peripheral region 224 forming the opening peripheral portion of the decompression cavity 221 and the tapered peripheral side surface 231 of the reduced diameter portion 23k facing each other at the front end surface of the collision member 22. An annular gap peripheral space 251n having a wedge-shaped cross section is formed. The space outer peripheral side of the gap peripheral space 251n is opened to the bypass flow path portion 251, and an annular constriction gap portion 21n formed at an opposing position between the inner peripheral edge of the decompression cavity 221 and the peripheral side surface of the reduced diameter portion 23k. And a structure communicating with the decompression cavity 221 through each other. The bypass flow path portion 251 is formed on both sides of the collision member 22 in the flow path FP in the flow direction so as to straddle the outer peripheral surface of the collision member 22 and the outer peripheral surface of the opposing collision member 23. Has been.

  In the present invention, by forming the throttle gap 21G using the collision member 22, not only the negative pressure is generated in the throttle gap 21G but also the collision member 22 is caused to collide with the air flow at a high speed and circulate downstream. Intense turbulence is generated in three dimensions. Thereby, a large number of small vortices can be formed densely in the region immediately downstream of the restricting gap 21G. That is, as shown in FIG. 4, the airflow GS flows toward the throttle gap 21 </ b> G in an accelerated form by passing through the preliminary throttle mechanism 30. On the other hand, as shown in FIG. 3, the collision member 22 and the opposing collision member 23 that form the throttle gap 21 </ b> G form a detour channel portion 251 that detours the flow WF that has collided with the channel wall portion 25. ing. That is, since the outer peripheral edge of the throttle gap 21G is open to the bypass flow path portion 251, the fluid resistance at the time of passing through the gap does not increase excessively, and as a result, the flow can pass through the throttle gap 21G at high speed. In other words, a strong negative pressure region is generated in a wide region in the throttle gap 21G and downstream thereof. At this time, as shown in FIG. 4, when the liquid LQ is supplied to the liquid intake port 226e of the suction hole 226, the liquid LQ efficiently passes through the suction hole 226 due to the negative fluid pressure generated in the throttle gap 21G. It is sucked and squeezed into droplets by being entrained in a small vortex formed in the immediate downstream region while being ejected into the throttle gap 21G.

  On the other hand, as shown in FIG. 5, the flow WF that has collided with the collision member 22 and has passed through the detour channel portion 251 turns downstream of the collision member 22 and forms a violent turbulent flow CF at a large flow rate. Thereby, on the downstream side of the collision member 22, a minute vortex SWE (turbulent flow) is formed at a very high density over the entire area. Further, since the generation density of the eddy current SWE is increased, the negative pressure region is formed not only inside the throttle gap 21G but also on the downstream side thereof so as to widen in a three-dimensional wide angle. Therefore, the formed droplets are finely pulverized by a larger number of vortexes on the downstream side of the gap. Further, the peripheral region of the narrowing gap 21G forms an annular gap peripheral space 251n that opens to the detour channel portion 251, and portions of the outer peripheral surface of the reduced diameter portion 23k located on both sides of the narrowing gap 21G in the flow direction are also included. Since it functions as an auxiliary gap, the droplet crushing efficiency is further improved.

  The individual vortex flow SWE generated by turbulent flow has a lower pressure at the center than at the outer periphery of the vortex, and therefore acts to draw the flow around the vortex flow SWE into the vortex center. Under the turbulent flow, as described above, a large number of fine eddy currents SWE are densely formed in a three-dimensional manner, and as shown in the upper part of FIG. 6, the droplet BM has a three-dimensional configuration by a plurality of eddy currents SWE. It will always be in the received state. Since each vortex SWE applies a suction force to the droplet BM toward its center, as shown in the lower part of FIG. 6, the droplet BM is sucked in all directions by the surrounding vortex SWE. In an “eight tear” state, crushing into microdroplets BF is promoted and droplet diameter averaging proceeds. That is, rather than colliding the droplets BM with each other and pulverizing them, the image is surrounded by a large number of small eddy currents SWE each having a suction force, and is torn in a plurality of different directions.

Further, the pressure reducing cavity 221 is formed at the tip of the collision member 22 so as to face the throttle gap 21G. The formation of the pressure reducing cavity 221 can be expected to have the following functions and effects.
-The whole area in the decompression cavity 221 becomes a high negative pressure region, which contributes to further improvement of the liquid suction efficiency.
An ultrasonic band resonance wave is generated by the resonance of the decompression cavity 221 in the flow, and droplet crushing due to resonance vibration is promoted.

  Hereinafter, various modified examples of the spray nozzle used in the present invention will be described (elements common to those already described are given the same reference numerals and detailed description thereof will be omitted). FIG. 7 shows an example in which the bottom of the cavity is formed in a curved surface in order to make the flow in the decompression cavity 221 formed in the collision member 22 smoother. FIG. 8 shows an example in which the opening inner peripheral surface of the decompression cavity 221 is a counterbore tapered surface 224 corresponding to the tapered peripheral side surface 231 of the tip of the opposing collision member 23. The formation of the tapered surface 224 enhances the effect of guiding the flow toward the distal end side of the opposing collision member 23.

  FIG. 9 shows an example in which the decompression cavity 221 is omitted from the collision member 22 and the tip surface is formed flat. A tapered peripheral side surface 231 is formed at the distal end portion of the opposing collision member 23, but the distal end surface facing the collision member 22 is formed flat. FIG. 10 shows an example in which a shallow decompression cavity 232 is formed on the front end surface of the opposing collision member 23. The collision member 22 is not formed with a decompression cavity, and the outer peripheral edge of the tip is a tapered peripheral side surface 225.

  FIG. 11 shows a modified example related to the formation form of the decompression cavity 221 when the suction hole 226 is formed. The inner peripheral surface of the decompression cavity 221 is the tapered peripheral side surface at the tip of the opposing collision member 23. An example of a counterbore tapered surface 224 corresponding to H.231 is shown. On the other hand, FIG. 12 shows a configuration in which the decompression cavity is omitted.

  FIG. 13 is an example in which the opposing collision member is eliminated, and the collision gap 22G is formed in such a manner that the collision member 22 faces the inner surface of the flow path forming member 20 as the restriction gap forming portion 20c. The front end surface of the collision member 22 has a convex curved surface corresponding to the inner surface of the wall portion of the flow path forming member 20. FIG. 14 shows an example in which the opposing collision member 123 is formed wider than the collision member 22 so that the detour channel portion 251 does not occur on the side of the opposing collision member 123.

  In addition, as shown in FIG. 15, if the suction hole formed in the collision member 22 is abolished, the spray nozzle 121 concerning the 2nd structure of the spray mechanism of this invention can be embodied. In this case, since the liquid cannot be supplied to the aperture gap 21G via the collision member 22, the gas-liquid mixed fluid MF obtained by mixing gas and liquid droplets using a known gas-liquid mixing nozzle (not shown) is preliminarily provided. It is formed and supplied directly to the throttle gap 21G from the fluid inlet side. Droplets contained in the gas-liquid mixed fluid MF are pulverized by the same action as the spray nozzle 21 having the first configuration shown in FIG. Is done.

  As shown in FIG. 16, the spray nozzle 121 according to the second configuration can be further connected to the downstream side of the spray nozzle 21 of the first configuration in the configuration of FIG. 1 via a relay pipe 306. is there. In this case, the relay pipe 306 can be connected to the spray outlet side of the spray nozzle 21 having the first configuration by forming a flow path connecting part such as a male screw part for connection in the same manner as the fluid inlet side. As a result, the mist formed by the spray nozzle 21 is supplied as a gas-liquid mixed fluid to the spray nozzle 121 according to the second configuration via the relay pipe 306, and the droplets of the mist MST to be finally sprayed are further finely divided. It becomes possible to do. In this configuration, the spray nozzle 21 having the first configuration is used as a gas-liquid mixing nozzle for supplying a gas-liquid mixed fluid to the spray nozzle 121 according to the second configuration.

  In addition, the gas-liquid mixed fluid MF is supplied to the spray nozzle 21 having the first configuration shown in FIG. 4 instead of the air flow GS, and spraying is performed while supplying a new liquid from the suction hole 226. May be.

1 Fog generator 21 Spray nozzle (spray mechanism)
21J Aperture part 21G Aperture gap 21n Neck gap part 22 Colliding member 23 Opposing collision member (aperture gap forming part)
23k Reduced diameter part 30 Preparation reduced diameter part FP flow path 31 Fluid inlet 106 Spray outlet 221 Depressurization cavity 226 Suction hole 251 Detour flow path part

Claims (11)

A hollow flow path forming member having a fluid inlet and a spray outlet for introducing a gas or gas-liquid mixed fluid, and having a flow path from the fluid inlet toward the spray outlet formed therein;
A collision member protruding from the inner surface of the flow path wall of the flow path forming member;
A gap forming portion facing the leading end portion in the protruding direction of the collision member in the flow path;
A bypass channel portion is formed between the outer peripheral surface of the collision member and the inner surface of the channel wall portion, and is lower than the bypass channel portion between the collision member and the throttle gap forming portion. A throttle gap that allows the gas-liquid mixed flow to pass while being throttled to have a flow rate and a high flow rate is formed,
The collision member penetrates the collision member in the protruding direction together with the flow path wall portion, and one end side opens a liquid ejection port in the throttle gap at the front end side of the collision member, and the other end side is A suction hole is formed in the outer surface of the wall portion through the flow path wall portion to open a liquid intake port,
A liquid negative pressure generated in the throttle gap draws liquid into the throttle gap from the liquid inlet through the suction hole to form droplets, and collides with the collision member and the bypass flow path portion. A spray mechanism characterized in that the liquid droplets are pulverized by being entrained in a wraparound turbulent flow that goes downstream of the impingement member via the above and sprayed from the spray outlet. A hollow flow path forming member having a fluid inlet and a spray outlet for introducing a gas-liquid mixed fluid and having a flow path from the fluid inlet toward the spray outlet formed therein;
A collision member protruding from the inner surface of the flow path wall of the flow path forming member;
A gap forming portion facing the leading end portion in the protruding direction of the collision member in the flow path;
A bypass channel portion is formed between the outer peripheral surface of the collision member and the inner surface of the channel wall portion, and is lower than the bypass channel portion between the collision member and the throttle gap forming portion. A throttle gap is formed to allow the gas-liquid mixed flow to pass while being throttled so as to have a flow rate and a high flow velocity, and a liquid droplet contained in the gas-liquid mixed fluid passing through the throttle gap collides with the collision member to cause the detour. A spray mechanism characterized in that it is pulverized by being entrained in a wraparound turbulent flow that goes around to the downstream side of the collision member through a flow path portion, and sprayed from the spray outlet. 3. The spray mechanism according to claim 1, wherein the bypass flow path portion is formed on both sides of the collision member in a protruding direction of the collision member when viewed from the flow direction in the flow path. The spray mechanism according to any one of claims 1 to 3, wherein a decompression cavity is formed in at least one of the opposing surfaces that form the throttle gap with the collision member and the gap forming portion. At least one of the opposing surfaces forming the aperture gap of the collision member and the gap forming portion is formed as an aperture inclined surface that gradually reduces the interval of the aperture gap from the upstream side to the downstream side on the inflow side. The spray mechanism according to any one of claims 1 to 4, wherein the spray mechanism is provided. At least one of the opposing surfaces forming the aperture gap of the collision member and the gap forming portion is formed as an enlarged inclined surface that gradually expands the interval of the aperture gap from the upstream side to the downstream side on the outflow side. The spray mechanism according to any one of claims 1 to 5, wherein: The gap forming portion is formed as an opposing collision member that protrudes from the inner surface of the wall portion toward the collision member on the side opposite to the collision member with respect to the cross-sectional center of the flow path, and the throttle gap projects from the collision member. The spray mechanism according to any one of claims 1 to 6, wherein the spray mechanism is formed between a front end portion in the direction and a front end portion in the protruding direction of the opposing collision member. 8. A reduced diameter portion having a tapered peripheral side surface in which a tip portion facing at least one of the narrowing gaps of the collision member and the opposing collision member has a diameter that decreases toward the tip. Spraying mechanism. One of the collision member and the opposing collision member is formed with a decompression cavity that is retracted in a gap forming direction on a front end surface facing the throttle gap, and the other is contracted in a positional relationship in which a front end faces the opening of the decompression cavity. The spray mechanism according to claim 8, wherein a diameter portion is formed. The narrowing gap has a wedge-shaped cross section when a peripheral region forming an opening peripheral portion of the decompression cavity and an outer peripheral region of a tapered peripheral side surface of the reduced diameter portion are opposed to each other at the front end surface of the collision member. An annular gap peripheral space whose outer peripheral side is open to the bypass flow path portion and the decompression cavity are formed at positions facing the inner peripheral edge of the decompression cavity opening and the peripheral side surface of the reduced diameter portion. The spray mechanism according to claim 9, wherein the spray mechanism is configured to communicate with each other via an annular constriction gap. The spray mechanism according to any one of claims 7 to 10, wherein the bypass flow path portion is formed in a shape extending over an outer peripheral surface of the collision member and an outer peripheral surface of the opposing collision member.

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