JP2006038285A - Flame producing device and method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To form the flame generated from city gas into the tornado shape. <P>SOLUTION: This flame producing device 1a comprises a supply passage 21a of the mixed flow of a combustion gas and the air, a discharge port 22a formed on a part of the supply passage 21a for discharging the mixed flow, and a swirling flow forming mechanism 3 forming the swirling flow of the air on a vertical axis 34a not passing through the discharge port 22a. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a flame production device, and more particularly, to a flame production device and a flame production method for forming a spiral shape of a flame generated by the combustion of city gas.

  In recent years, many science museums and corporate PR halls have been set up for various types of enlightenment activities for public science education and corporate public relations activities. In the energy field such as oil, coal, natural gas, and city gas, a great PR effect can be expected if a flame that is a symbol of these energies can be effectively produced.

From such a viewpoint, for example, a technique for forming a flame so that the flame is ejected or scattered is known (see Patent Document 1). An apparatus for forming a flame into a tornado shape has been put into practical use. This is a device installed at the Magma Science Adventure Center in the UK. It is a device that sends air from the four corners of the flame generated by kerosene with a fan and produces a tornado.
JP 2003-14209 A

  Producing a flame like a tornado is effective for appealing the mystery, power, and wonder of fire, and the British case mentioned above is one of them. However, even if a similar tornado flame is produced using city gas for PR of city gas, the burning speed of city gas is much faster than that of kerosene, so a clean form of tornado is formed. There was a problem of not being.

  This invention solves the said subject and aims at providing the flame production apparatus and flame production method which can form the flame generated with city gas in the shape of a tornado.

  The flame directing device of the present invention is a supply path for a mixed flow of combustion gas and air, a discharge port for discharging a mixed flow provided in a part of the supply path, and around a flame generated from the discharge port. And a swirling flow forming mechanism that forms a swirling flow of air around a vertical axis that does not pass through the discharge port.

  In this way, the flame rises while wrapping around the vertical axis by shifting the discharge port that becomes the central axis of the flame formation by discharging the mixed flow and the vertical axis that generates the swirling flow around the flame. Because of this behavior, it becomes easier to visually recognize the spiral movement of the flame.

  As the combustion gas, for example, city gas can be used.

  The swirl flow forming mechanism is a plurality of air supply pipes that extend in the vertical direction on the circumference of an imaginary circle whose vertical axis passes through the center, and are installed at a substantially equal angle to each other. A plurality of positions on the upper side in the vertical direction with respect to the outlet may be configured to be provided with blowing slits that open in the same direction along the circumference of the virtual circle in the substantially tangential direction of the virtual circle.

  Further, the swirl flow forming mechanism includes a first air convection cylinder having at least a part extending vertically downward from the discharge port and having an open end face facing the upper side in the vertical direction around the vertical axis, and the first air convection. In the cylinder for the first air convection in the vicinity of the side wall of the first air convection cylinder at a position vertically below the discharge port, and only the direction component along the tangential direction of the side wall or the direction component and the vertical It can comprise so that it may have a 1st air supply nozzle opened toward the direction which has only the direction component which faces a direction upper side.

  Here, the first air supply nozzle preferably forms an upward angle of about 10 degrees with respect to the tangential direction of the side wall of the first air convection cylinder.

  Further, the swirl flow forming mechanism includes a second air convection cylinder provided concentrically with the first air convection cylinder outside the first air convection cylinder, and a second air convection cylinder. A plurality of the air convection cylinders are provided at substantially equal angles to each other at positions near the side wall of the second air convection cylinder and vertically below the discharge port. A second air supply nozzle that opens in a direction having only a directional component along the tangential direction or only a directional component along the tangential direction of the side wall of the second air convection cylinder and a directional component facing upward in the vertical direction. It can comprise so that.

  Here, it is preferable that the second air supply nozzle forms an upward angle of about 10 degrees with respect to the tangential direction of the side wall of the second air convection cylinder.

  At this time, the swirl flow forming mechanism includes an air guide cylinder provided concentrically with the second air convection cylinder on the outside of the second air convection cylinder, and the second air convection cylinder and the air guide. You may make it have an annular air supply part which is provided cyclically | annularly between cylinders and blows air upwards in the perpendicular direction.

  In addition to this, the swirling flow forming mechanism has an air convection cylinder having at least a part extending substantially vertically from the discharge port toward the upper side in the vertical direction and having an end surface facing the upper side in the vertical direction opened around the vertical axis, Provided in the air convection cylinder in the vicinity of the side wall of the air convection cylinder, and opens toward the direction having only the direction component along the tangential direction of the side wall or only the direction component and the direction component facing upward in the vertical direction. And an air supply nozzle to be configured.

  Here, the air supply nozzle preferably forms an upward angle of about 20 degrees with respect to the tangential direction of the side wall of the air convection cylinder.

  The flame rendering method of the present invention includes a step of discharging a mixed flow of fuel gas and air from a discharge port, a step of burning a mixed flow discharged from the discharge port to generate a flame from the discharge port, and a surrounding of the flame. And a step of forming a swirling flow of air around a vertical axis that does not pass through the discharge port.

  As described above, according to the flame directing apparatus of the present invention, it becomes easy to visually recognize the spiral movement of the flame generated by the fuel gas, and it is possible to easily form a tornado-like flame that dynamically changes with time. This can further enhance the PR effect of the fuel gas.

  Details of the flame directing apparatus of the present invention will be described below with reference to the drawings. FIG. 1 (a) shows a side view of the first embodiment of the flame directing apparatus of the present invention, and FIG. 1 (b) shows a plan view seen from the 1-1 direction in FIG. 1 (a).

  The flame directing apparatus 1a includes a cylindrical storage frame 2a and four air supply pipes 3 provided at equal intervals thereon.

  The storage frame 2a includes a burner 21a extending toward the upper surface of the storage frame 2a, and the flame generating side end of the burner 21a opens as an ejection port 22a on the upper surface of the storage frame 2a. The specification of the burner 21a is not particularly limited, and as an example, a boiler pilot burner UPB-40 (burner nozzle diameter 48.6 mm) manufactured by Hosoyama Heater Co., Ltd. is used.

  A gas supply path 23 and a combustion air supply path 24 are connected to the burner 21a. Further, an ignition burner (not shown) is provided in the vicinity of the discharge port 22a, and normal temperature city gas supplied from the gas supply path 23 and normal temperature air supplied from the combustion air supply path 24 are burners. It rises as a mixed flow inside 21a, is ignited by an ignition burner, and burns as a flame at the discharge port 22a. Since the flame directing apparatus 1a is installed with the supply port 22a facing upward, the flame generation direction is vertically upward from the discharge port 22a. Here, the city gas is a combustible gas produced using natural gas mainly composed of methane as a raw material. In addition to the city gas, a combustion gas mainly composed of methane can be used as the fuel.

  Four air supply pipes 3 are provided at 90 ° intervals on a virtual circle 32 passing through the center of a virtual vertical axis 34a on the storage frame 2a, and each of the air supply pipes 3 extends vertically upward. An annular top plate 33 is provided at the upper ends of the four air supply pipes 3 to form a flame exhaust port. In one example, the diameter of the storage frame 2a is about 1000 mm, the height from the storage frame 2a to the top plate 33 is about 1000 mm, and the opening of the top plate 33 is about 350 mm.

  2 is a perspective view of the vicinity of the air supply pipe, FIG. 3 (a) is a side view of the air supply pipe, and FIG. 3 (b) is a portion shown as A in FIG. 3 (a). A detailed side view is shown. An air flow path is formed inside the air supply pipe 3, and when air is supplied from an air supply source (not shown) to the end of the air supply pipe 3 on the storage frame 2a side, the air is air The inside of the supply pipe 3 is raised. As shown in FIGS. 2 and 3, the air supply pipe 3 has a large number of blow slits 31 that are in communication with the internal flow path and are elongated in the vertical direction at equal intervals in the axial direction of the air supply pipe 3. It is provided in a direction perpendicular to the axial direction. In the illustrated example, the blower slits 31 are provided in almost the entire region in the direction in which the air supply pipe 3 extends. The air supply pipe 3 has a length of about 1050 mm and an outer diameter of about 75 mm. A total of 18 pieces are provided with a setting interval of 5 mm. Further, the blower slits 31 of the air supply pipes 3 are oriented along the circumference of the virtual circle 32 in the direction indicated by the white arrow in FIG. 1B, that is, in the substantially tangential direction of the virtual circle 32. Open in the same direction. Therefore, the air that has risen inside the air supply pipe 3 is ejected from each blowing slit 31 around the vertical shaft 34a in the same rotational direction, and a swirling flow is formed.

  The discharge port 22 a is provided at a position shifted from the center point of the virtual circle 32. For this reason, the central axis of the swirl flow of air and the central axis of the flame are eccentric. In the illustrated example, the diameter X1 of the virtual circle 32 is 900 mm, while the eccentric amount Y1 between the vertical shaft 34a and the discharge port 22a is about 50 mm.

Next, an operation method of the flame effect device 1 will be described. First, the gas supply path 23 and the combustion air supply path 24 are opened to fill the interior of the burner 21a with the mixed flow. The ignition burner is then actuated to burn the mixed stream. As a result, a flame is generated from the discharge port 22a upward in the vertical direction, and at the same time, the mixed flow is replenished from the gas supply passage 23 and the combustion air supply passage 24 and the combustion continues. It is formed. Here, the gas flow rate was about 2 m ³ / h, the gas supply pressure was 2 kPa, and the air ratio was 0.2 or less. The air ratio is an index indicating how many times the amount of air (theoretical air amount) necessary for complete combustion of the fuel is supplied.

Here, the air supply source is opened, and air is blown from the blowing slit 31 of the air supply pipe 3. Here, the supplied air flow rate was about 52 m ³ / h, and the air wind speed was about 2 m / s. The air becomes a swirl flow swirling around the vertical axis 34a, and causes a swirl motion around the vertical axis 34a in the flame. FIG. 4 schematically shows the state of the flame at this time, and it has been confirmed that the flame 11 moves so as to swing irregularly around the vertical axis 34a. At this time, the height of the flame was about 800 mm, and the width of the flame was about 300 mm. The flame color was orange.

  In order to change the height of the flame, the gas supply amount may be adjusted, and after a certain time, the flame returns to a steady state corresponding to the gas supply amount.

  Here, the reason why the central axis of the swirling flow of air and the central axis of the flame are eccentric will be described. Even if the discharge port 22a is made to coincide with the center point of the virtual circle 32, the flame is swung because it receives a swirling flow. However, in this case, since the flame only rotates around the center axis of the flame, it is difficult to see the flame rising spirally. In other words, the pipe rotates around its axis, and it is impossible to know that the pipe is rotating unless a pattern is formed on the surface of the pipe. On the other hand, when the discharge port 22a is eccentric, the flame axis rises while spiraling around the vertical axis 34a. In other words, since the vinyl pipe rotates around the shaft, the spiral structure becomes easier to see. Moreover, by decentering, the balance of the flow is somewhat disrupted, fluctuations occur in the spirally rising flame, and a tornado-like flame that changes dynamically with time is formed. However, if the amount of eccentricity is too large, the balance of the flow is excessively lost, the balance between the upward flow of the flame and the air swirl flow cannot be achieved, and the helical structure is also lost. Further, since the wind speed of the swirling flow becomes faster as it goes to the outer periphery of the flame directing device 1a, that is, as it gets closer to the air supply pipe 3, there is a possibility that the flame diffuses too much and becomes a thick and short flame or blows off. . From the above viewpoint, the above eccentricity amount is considered to be in the range of the optimal eccentricity amount.

  Also, with such a configuration, a clean form of tornado is formed even in city gas with a high combustion rate because the air ratio is suppressed to 0.2 or less, diffusion combustion is performed, and the flow balance is intentionally broken. This is because the combustion speed is reduced. That is, in order to stabilize the flame, the air ratio is usually brought close to 1.0 to produce a premixed combustion flame (a blue flame is formed), but at this air ratio, the combustion speed is too fast and the tornado Not formed. On the other hand, if the air ratio is lowered to 0.2 or less, the stability of the flame is reduced, but diffusion combustion with a slow combustion speed occurs, so that the supply gas reaches the opening of the top plate 33 from the discharge port 22a. By adjusting the degree of diffusion (mixing with air), it is possible to make a long flame that suppresses the progress of the combustion reaction. In addition, since the diffusion combustion has occurred, the color of the flame becomes orange. In addition, the diffusion process is mainly affected by the turbulence of gas and air flow (turbulent diffusion). By decentering in this way, the flow balance is intentionally broken a little to adjust the degree of diffusion process. In addition, it is possible to adjust the combustion speed that disturbs the flow.

  Next, a second embodiment of the flame directing device of the present invention will be described with reference to FIG. FIG. 5 (a) shows a side view of the second embodiment of the flame directing apparatus of the present invention, and FIG. 5 (b) shows a plan view seen from the direction 5-5 in FIG. 5 (a). The present embodiment is greatly different from the first embodiment in that the burner extends longer and the swirling flow is formed from below the discharge port.

  A first air convection cylinder 41 is provided on the upper surface of the storage frame 2b around the vertical axis 34b. The tip of the first air convection cylinder 41 extends to almost the same height as the discharge port 22b and the entire surface is an opening. However, a part of the tip may be covered with a top plate as in the first embodiment. The first air convection cylinder 41 is an air convection cylinder in which at least a part extends vertically downward from the discharge port 22b and an end surface facing the upper side in the vertical direction opens when the discharge port 22b is used as a reference.

  A first air supply nozzle 42 is provided on the storage frame 2 b in the vicinity of the side wall constituting the first air convection cylinder 41. One end of the first air supply nozzle 42 opens into the first air convection cylinder 41, and air is supplied from the other end. The first air supply nozzle 42 is provided along the circumference of the side wall and slightly upward with respect to the upper surface of the storage frame 2b. The angle of the white arrow in FIGS. 5A and 5B means this. That is, the first air supply nozzle 42 opens toward a direction having a directional component along the tangential direction of the side wall and a directional component facing upward in the vertical direction. However, the direction component facing the upper side in the vertical direction may be 0 (for example, refer to the third embodiment). The first air supply nozzle 42 may not be provided on the storage frame 2b, but it is necessary to be provided at least inside the first air convection cylinder 41.

  The supply port 22b is eccentrically provided with respect to the first air convection cylinder 41. In one example, the first air convection cylinder 41 has an inner diameter (X2) of 190 mm and a height of about 270 mm, and the eccentricity Y2 is about 20 mm. As the burner 21b, the above-described boiler pilot burner UPB-40 modified to a nozzle diameter of about 60 mm is used. The upward angle of the first air supply nozzle 42 is about 10 °, and the diameter of the opening is about 50 mm. did.

With the above apparatus specifications, the operation was performed at a gas flow rate of about 0.5 m ³ / h, a gas supply pressure of 2 kPa, an air ratio of 0.2 or less, an air flow rate of about 52 m ³ / h, and an air wind speed of about 2 m / s. The air blown from the first air supply nozzle 42 becomes an upward swirl flow around the side wall of the first air convection cylinder 41, and this upward swirl flow causes a swirl motion in the flame, and the flame is the first As in the case of the embodiment, it was confirmed to move so as to turn irregularly around the vertical axis 34b. At this time, the height of the flame was about 500 mm, and the width of the flame was about 150 mm. The flame color was orange.

  Next, a third embodiment of the flame effect device of the present invention will be described with reference to FIG. FIG. 6A shows a side view of the third embodiment of the flame directing apparatus of the present invention, and FIG. 6B shows a plan view seen from the 6-6 direction in FIG. 6A. The present embodiment is a further improvement of the second embodiment, and is different in that a swirl flow forming cylinder is doubled and an air flow is supplied along each cylinder.

  A first air convection cylinder 51 is provided on the upper surface of the storage frame 2c around the vertical axis 34c. The tip of the first air convection cylinder 51 extends to almost the same height as the discharge port 22c, and the entire surface is an opening. A second air convection cylinder 52 extends concentrically to the same height as the first air convection cylinder 51 outside the first air convection cylinder 51. Further, an air guide cylinder 53 extends concentrically outside the second air convection cylinder 52.

  A first air supply nozzle 54 is provided on the storage frame 2 c in the vicinity of the side wall constituting the first air convection cylinder 51. One end of the first air supply nozzle 54 opens into the first air convection cylinder 51, and air is supplied from the other end. The first air supply nozzle 54 is provided along the circumference of the side wall and in parallel with the upper surface of the storage frame 2c. Four second air supply nozzles 55 are provided at intervals of 90 ° on the storage frame 2 c in the vicinity of the side wall constituting the second air convection cylinder 52. One end of the second air supply nozzle 55 opens into the second air convection cylinder 52, and air is supplied from the other end. The second air supply nozzle 55 is provided in the tangential direction of the side wall along the circumference of the side wall and slightly upward with respect to the upper surface of the storage frame 2. Further, an annular air supply unit 56 is provided between the second air convection cylinder 52 and the air guide cylinder 53, and is provided in an annular shape to blow air upward in the vertical direction. An air supply path 57 for supplying air is connected to the annular air supply unit 56. The angles of the hollow arrows in FIGS. 6A and 6B mean the above.

  The discharge port 22 c is provided eccentric to the first and second air convection cylinders 51 and 52 and the air guide cylinder 53. In one example, the first air convection cylinder 51 has an inner diameter of 200 mm and a height of about 420 mm, the second air convection cylinder 52 has an inner diameter of 450 mm and a height of about 420 mm, and the third air convection cylinder 53 has an inner diameter of 600 mm and a height of The thickness is about 420 mm, and the eccentricity Y3 is about 20 mm. As the burner 21c, the above-described boiler pilot burner UPB-40 whose nozzle diameter is modified to about 60 mm is used. The diameter of the opening of the first air supply nozzle 54 is 16 mm, and the second air supply nozzle 55 The upward angle was about 10 °, and the diameter of the opening was about 16 mm.

With the above apparatus specifications, the operation was performed at a gas flow rate of about 2.5 m ³ / h, a gas supply pressure of 2 kPa, an air ratio of 0.2 or less, an air flow rate of about 145 m ³ / h, and an air wind speed of about 2 m / s. The air blown from the first air supply nozzle 54 becomes an upward swirl flow around the side wall of the first air convection cylinder 51, and this upward swirl flow causes a swirl motion in the flame. Further, the air blown from the second air supply nozzle 54 becomes an upward swirling flow around the side wall of the second air convection cylinder 52, and the first air supply nozzle 54 causes a swirling motion. A further swirl motion is given to the flame. On the other hand, the rising air flow blown upward in the vertical direction from the annular air supply unit 56 confines the flame in the rising air flow and prevents the influence of the external air flow on the flame and acts as a kind of air curtain. . As a result, it was confirmed that the flame moves so as to turn irregularly around the vertical axis 34c, as in the first embodiment. At this time, the height of the flame was about 1500 mm, and the width of the flame was about 300 mm. The flame color was orange.

  Next, a fourth embodiment of the flame directing apparatus of the present invention will be described with reference to FIG. FIG. 7A shows a side view of the fourth embodiment of the flame effect device of the present invention, and FIG. 7B shows a plan view seen from the direction 7-7 in FIG. 7A. This embodiment is different from the first embodiment in that the discharge port is provided close to the storage frame, but a cylindrical glass container is used to generate the swirling flow.

  An air convection cylinder 61 is provided on the upper surface of the storage frame 2d around the vertical axis 34d. The tip of the air convection cylinder 61 extends to almost the same height as the discharge port 22d, and has a top plate 63 that forms an opening serving as a flame exhaust port at the upper end. However, the entire surface as in the first embodiment is provided. May be open. The air convection cylinder 61 is made of heat-resistant glass so that a flame generated inside can be visually observed.

  An air supply nozzle 62 is provided on the storage frame 2 d in the vicinity of the side wall constituting the air convection cylinder 61. One end of the air supply nozzle 62 opens into the air convection cylinder 61, and air is supplied from the other end. The air supply nozzle 62 is provided along the circumference of the side wall and slightly upward with respect to the upper surface of the storage frame 2d. The angles of the white arrows in FIGS. 7A and 7B mean this. That is, although it opens toward the direction which has the direction component along the tangential direction of a side wall, and the direction component which faces a perpendicular direction upper direction, the direction component which faces a perpendicular direction upper side may be zero. The air supply nozzle 62 may not be provided on the storage frame 2d, but it is necessary to be provided at least inside the air convection cylinder 61.

  The supply port 22d is provided eccentric to the air convection cylinder 61. In one example, the air convection cylinder 61 has an inner diameter (X4) of 190 mm and a height of about 500 mm, and the eccentric amount Y4 is about 20 mm. As the burner 21d, the boiler pilot burner UPB-40 described above was used, and the upward angle of the air supply nozzle 62 was about 20 °.

With the above apparatus specifications, the gas was operated at a gas flow rate of about 0.5 m ³ / h, a gas supply pressure of 2 kPa, an air ratio of 0.2 or less, an air flow rate of about 52 m ³ / h, and an air wind speed of about 2 m / s. The air blown from the air supply nozzle 62 becomes an upward swirl flow around the side wall of the air convection cylinder 61, and this upward swirl flow causes a swirl motion in the flame, and the flame is the same as in the first embodiment. It was confirmed that the robot moves so as to turn irregularly around the vertical axis 34d. At this time, the height of the flame was about 400 mm, and the width of the flame was about 100 mm. The flame color was orange.

  As mentioned above, although several embodiment of this invention was described, this invention is not limited to this, A various deformation | transformation is possible. For example, the number of air supply pipes shown in the first embodiment is not limited to four and can be increased or decreased as necessary as long as a predetermined swirl flow can be formed. Further, the size and installation interval of the blowing slits may be changed in the axial direction of the air supply pipe, and the wind speed and volume of the swirling flow may be adjusted with respect to the flame generation direction, and the slit may be given an upward angle. . A plurality of air supply nozzles may be provided to generate a stronger swirling flow. In addition, an embodiment in which at least one air supply pipe shown in the first embodiment is installed in the glass cylindrical container shown in the fourth embodiment is also possible.

  Furthermore, the flame can be changed to light blue by providing an air blowing port in the vicinity of the discharge port and supplying air having a low flow rate. This is because the combustion state approaches a premixed combustion fire by increasing the air supply amount, and a change from an orange tornado to a blue tornado and vice versa can be realized.

  In addition, the tornado flame can be colored by the colored flame of the metal salt by spraying an aqueous solution of the metal salt around the flame. For example, yellow can be used for sodium, purple for potassium, red for lithium, and green for copper, and the present invention can be made more effective.

It is the side view and top view of a flame production apparatus which concern on the 1st Embodiment of this invention. It is a fragmentary perspective view of the air supply pipe vicinity of the flame production apparatus shown in FIG. It is a partial detailed side view of the air supply pipe | tube of the flame production apparatus shown in FIG. It is explanatory drawing which shows the generation | occurrence | production state of the flame of the flame production apparatus shown in FIG. It is the side view and top view of a flame production apparatus which concern on the 2nd Embodiment of this invention. It is the side view and top view of a flame production apparatus which concern on the 3rd Embodiment of this invention. It is the side view and top view of a flame production apparatus which concern on the 4th Embodiment of this invention.

Explanation of symbols

1a, 1b, 1c, 1d Flame directing device 2a, 2b, 2c, 2d Storage frame 21a, 21b, 21c, 21d Burner 22a, 22b, 22c, 22d Discharge port 23 Gas supply path 24 Combustion air supply path 3 Air supply pipe 31 Blower slit 32 Virtual circle 33 Top plate 34 a, 34 b, 34 c, 34 d Vertical axis 41 First air convection cylinder 42 First air supply nozzle 51 First air convection cylinder 52 Second air convection cylinder 53 Air guide cylinder 54 First air supply nozzle 55 Second air supply nozzle 56 Annular air supply portion 57 Air supply path 61 Air convection cylinder 62 Air supply nozzle 63 Top plate

Claims (11)

A supply path for a mixed flow of combustion gas and air;
A discharge port provided in a part of the supply path for discharging the mixed flow;
A flame directing device having a swirl flow forming mechanism that forms a swirl flow of air around a vertical axis that does not pass through the discharge port, around a flame generated from the discharge port.   The flame rendering device according to claim 1, wherein the combustion gas is a city gas.   The swirl flow forming mechanism is an air supply pipe extending in a vertical direction on a circumference of a virtual circle with the vertical axis passing through the center, and a plurality of air supply pipes installed at substantially equal angles to each other. Is provided with a blowing slit that opens in the same direction along the circumference of the virtual circle in a substantially tangential direction of the virtual circle at a plurality of positions on the upper side in the vertical direction with respect to the discharge port. Item 3. The flame directing device according to Item 1 or 2. The swirl flow forming mechanism is:
A first air convection cylinder having at least a part extending vertically downward from the discharge port and having an open end surface facing the upper side in the vertical direction around the vertical axis;
In the first air convection cylinder, in the vicinity of the side wall of the first air convection cylinder, at a position vertically below the discharge port, the direction along the tangential direction of the side wall The flame directing device according to claim 1, further comprising: a first air supply nozzle that opens in a direction having only the component, or only the direction component and the direction component facing upward in the vertical direction.   The flame directing apparatus according to claim 4, wherein the first air supply nozzle forms an upward angle of about 10 degrees with respect to a tangential direction of a side wall of the first air convection cylinder. The swirl flow forming mechanism is:
A second air convection cylinder provided concentrically with the first air convection cylinder on the outside of the first air convection cylinder;
In the second air convection cylinder, a plurality of the air convection cylinders are provided at substantially equal angles to each other at positions near the side wall of the second air convection cylinder and vertically below the discharge port. Is only a directional component along the tangential direction of the side wall of the second air convection cylinder, or only a directional component along the tangential direction of the side wall of the second air convection cylinder and a directional component facing upward in the vertical direction. The flame directing device according to claim 4, further comprising: a second air supply nozzle that opens in a direction including the second air supply nozzle.   The flame directing apparatus according to claim 6, wherein the second air supply nozzle forms an upward angle of about 10 degrees with respect to a tangential direction of a side wall of the second air convection cylinder. The swirl flow forming mechanism is:
An air guide cylinder provided concentrically with the second air convection cylinder on the outside of the second air convection cylinder;
The flame directing device according to claim 7, further comprising an annular air supply unit that is annularly provided between the second air convection cylinder and the air guide cylinder and that blows air upward in the vertical direction. The swirl flow forming mechanism is:
An air convection cylinder having at least a part extending substantially vertically from the discharge port toward the upper side in the vertical direction around the vertical axis, and having an open end surface facing the upper side in the vertical direction;
The air convection cylinder is provided in the vicinity of the side wall of the air convection cylinder and has only a directional component along the tangential direction of the side wall or only the directional component and a directional component facing upward in the vertical direction. The flame directing device according to claim 1, further comprising an air supply nozzle that opens in a direction.   The flame directing apparatus according to claim 9, wherein the air supply nozzle forms an upward angle of about 20 degrees with respect to a tangential direction of a side wall of the air convection cylinder. Discharging a mixed flow of fuel gas and air from a discharge port;
Burning the mixed flow discharged from the discharge port to generate a flame from the discharge port;
Forming a swirling flow of air around a vertical axis that does not pass through the discharge port around the flame.

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