JPH037728Y2 - - Google Patents

Description

[Detailed description of the invention] Industrial application field The present invention relates to an improvement of a combustion burner that facilitates the ignition spark ignition of a burner equipped with a cavity resonant compound nozzle called an MPC nozzle. .

Prior Art In a first example of a combustion burner equipped with a cavity resonant composite nozzle called an MPC nozzle having a conventional ignition spark ignition mechanism, the air supply port A is arranged as shown in FIG. Inside the provided burner housing B, a cavity resonant compound nozzle C and an ignition electrode D for ignition are arranged adjacent to the nozzle C, and on the side surface of the base of the nozzle C, A fuel supply pipe E is connected, and a compressed air supply pipe F is connected to the end face, and the fuel supplied from the fuel supply pipe E and the compressed air supplied from the compressed air supply pipe F are connected to the nozzle. A fuel spray G is atomized by C, and the spray G is ignited by an ignition electrode D. On the other hand, a blower fan (not shown) blows combustion air from an air supply port A in the direction of the arrow. It is formed so as to be supplied into the housing B in the direction shown.

The cavity resonant compound nozzle C fluidly forms a circulating flow H inside the spray G, and when the mixture of the spray G and the combustion air is ignited and starts combustion, this circulating flow H turns into high-temperature gas. It is configured to create a circulating flow and maintain combustion. Further, the second example shown in FIG. 4 has a cavity resonant composite nozzle C inside the burner housing B and an ignition electrode I at a position adjacent to the nozzle C, similar to the one shown in FIG. is arranged, a fuel supply pipe E is connected to the side surface of the nozzle C, and a compressed air supply pipe F is connected to the end surface of the nozzle C, and the structure is the same as that of the first example. However, the tip of the ignition electrode I is bent toward the inside of the spray G. Further, the third example has a structure in which a pilot burner (not shown) is disposed as an ignition electric device adjacent to the above-mentioned cavity resonance type composite nozzle, and the atomization of the spray G is carried out. There have been known structures in which a mixture of spray G and combustion air is ignited by the ignition action of the pilot burner on the fuel.

Problems to be Solved by the Present Invention In the first example shown in FIG. Since the flame stabilizer is self-stabilizing, a flame stabilizer is not necessary, but when the spray G is ignited by an ignition spark using the ignition electrode D without a flame stabilizer, Ignition electrode D as shown in FIG.
In a shape in which the tip of the spray G is spaced apart from the spray G, the spread angle of the spray G is suppressed due to the influence of the flow velocity of the combustion air blown from the blower fan, and a circulating flow H effective for ignition is generated in the spray G. Since the fuel is not formed, it is difficult to ignite it, and if the speed of the fuel sprayed from the nozzle C is too high, it is also difficult to ignite it. In the second example, as shown in FIG. 4, the ignition electrode I is arranged adjacent to the nozzle C in a bent shape in the fuel spray G atomized by the nozzle C. Therefore, when spark ignition is performed in the circulating flow H formed inside the spray G, the electrode I is located at a position where it is easy to ignite the spark.
As a result of the voltage leaking, it becomes difficult to ignite, and even if ignition occurs, the electrode I will be melted by the heat of the flame. The drawback was that it was difficult to ignite using a combustion spark.

In addition, if a pilot burner is used as in the third example, ignition is easier, but since the pilot burner uses gas, there is a risk of gas leakage, so it is not suitable for use in industrial furnaces that operate unmanned and automatically. In some cases, there were drawbacks that left problems with safety.

In view of the current state of the conventional structure described above, the present invention provides a ring-shaped plate around the ejection port of the nozzle, and arranges an ignition electrode facing directly downstream of the ring plate, thereby reducing the cavity as described above. An ignition electrode is disposed adjacent to a resonant compound nozzle, and an ignition spark of the ignition electrode ignites the fuel atomized by the nozzle, or an ignition electrode adjacent to the nozzle. Unlike the structure in which the tip of the arranged ignition electrode is bent to face the spray, and unlike the structure in which a pilot burner is arranged, a part of the combustion air supplied by the blower fan is The shape of the ring plate creates a spiral airflow that is effective for ignition, and the negative pressure of the spiral portion forms a part of the spray into a circulating flow for ignition, and the ignition electrode ignites the ignition spark. It has a structure that is easy to construct, and was devised for the purpose of providing a combustion burner with a simple structure and improved maintainability.

Means for Solving the Problems As described in the claims of the utility model registration, the present invention provides a ring that surrounds the jet nozzle in the flow path of combustion air in the outer peripheral area of the jet nozzle of the fuel spray nozzle. By adopting a configuration in which a plate is disposed and an ignition electrode is disposed facing directly downstream of the ring plate, a fuel spray nozzle, which is a cavity resonant composite nozzle, and a An ignition electrode is disposed adjacent to the nozzle, the atomized fuel is made into a spray by the nozzle, and the mixture of this spray and combustion air is ignited by the ignition electrode to cause combustion. The structure differs from the structure in which the tip of an ignition electrode placed adjacent to the nozzle is bent toward the spray, and a pilot burner is further installed in a position adjacent to the nozzle to generate the spray. This structure makes it easy to ignite the combustion air, but unlike other structures that pose safety problems such as gas leakage, the combustion air supplied by the blower fan passes through the ring plate. Accordingly, a spiral is formed on the downstream side of the ring plate, and the action of the spiral generates a circulating flow that is advantageous for ignition during the spray, so that the ignition electrode can easily ignite. This solves the problem of igniting the spray of a cavity resonant compound nozzle, which was difficult to ignite using a conventional ignition electrode, and since it does not use a pilot burner, there is no risk of gas leakage, and the structure is simple. Moreover, it has a structure that allows for improved maintainability.

Embodiment and operation FIGS. 1 and 2 are schematic structural diagrams showing the outline of the structure of a combustion burner as an example of the embodiment, and as shown in FIG. 1, one side is opened and a part of the peripheral wall is opened. A fuel spray nozzle 3, which is a cavity resonant composite nozzle called an MPC nozzle, and a position adjacent to and parallel to the spray nozzle 3 are provided inside a burner housing 2 having a substantially cylindrical shape in which an air supply port 1 is disposed. An ignition electrode 4 for igniting the ignition spark is disposed so as to occupy the same area, and a fuel supply pipe 5 disposed from the outside of the burner housing 2 is connected to the side surface of the base of the spray nozzle 3. Similarly, a compressed air supply pipe 6 for atomization is connected to the base end surface, and the fuel and compressed air supplied from both supply pipes 5 and 6 are passed through the spray nozzle 3 as atomized fuel. The fuel is ejected from an ejection port 7 of the spray nozzle 3 to form a fuel spray 8. The spray nozzle 3 configured as described above has a ring plate 10 located in the flow path 9 in the outer peripheral area of the spray nozzle 7 and perpendicular to the axis of the spray nozzle 3. The ring plate 10 is supported by a fixed rod 11 protruding from the outer peripheral wall, and as shown in FIG. 2, the ring plate 10 is made of plate material and has an annular cross-sectional shape with a circular hole in the center. In addition, a plurality of slits 13 are bored in the surface of the ring plate 10 radially from the center in a radial direction, and the airflow passing through the slits 13 prevents the attachment of carbon due to combustion on the surface of the ring plate 10. The shape is designed to prevent this. Therefore, as shown in FIG. 2, a ring-shaped ring plate 10 is arranged around the ejection port 7 of the spray nozzle 3, and the ring plate 10 is further surrounded by an opening wall of the burner housing 2. Due to the existence of the ring plate 10, the combustion air flow shown by the arrow supplied from the air supply port 1 is formed into a spiral shape surrounded by a negative pressure on the downstream side of the link plate 10. As a result of the generation of the spiral, a part of the spray 8 is drawn into the spiral to form an ignition circulating flow 12, and the electrode 4 is disposed directly below the ignition circulating flow 12. The spray 8 is formed to be ignited and burned by the ignition spark.

Operation The operation of the embodiment described above will be explained with reference to FIGS. 1 and 2. In the combustion burner shown in FIG. 1, the combustion air flow shown by the arrow is supplied to the burner housing 2 through the air supply port 1 by a blowing fan (not shown), and is directed to the outer periphery of the spout 7 of the spray nozzle 3. The ring plate 10 disposed in the flow path 9 forms a spiral directly downstream of the ring plate 10, and the spiral is made to have a negative pressure. It acts to draw in a part of the fuel spray 8 ejected from the spray nozzle 3 and form it into an ignition circulation flow 12,
If the ignition spark is ignited by the ignition electrode 4 disposed close to the ignition circulating flow 12, even if the spray 8 having a high velocity is diffused by the action of the spray nozzle 3, the above-mentioned As described above, the ignition circulation flow 12 functions to facilitate ignition.

Effects of the present invention The present invention has the configuration described above, and like a combustion burner having a conventional ignition spark ignition mechanism, a fuel spray nozzle and an ignition electrode are arranged in the burner housing, and the ignition spark There are those with a structure that ignites the atomized fuel sprayed from the spray nozzle by ignition, those with a structure where the tip of the ignition electrode is bent toward the spray, or those with a structure where the tip of the ignition electrode is bent toward the spray. Unlike a structure in which a pilot burner using fuel is installed to facilitate ignition, a fuel spray nozzle is surrounded by a jet nozzle in the combustion air flow path in the outer peripheral area of the jet nozzle. Since the ring plate is arranged and the ignition electrode is arranged facing directly downstream of the link plate, the combustion air supplied into the burner housing spirals downstream of the ring plate. A part of the sprayed fuel is drawn in by the spiral to form a circulating flow for ignition, and the ignition spark is ignited with the ignition electrode for the circulating flow. The ignition spark ignition is not hindered by the speed of the atomized fuel or the influence of the combustion air, and the structure allows for easy ignition by the action of the ignition circulation flow, which makes conventional spark ignition difficult. It has the effect of easily igniting the spray from the hollow resonant composite nozzle, and also eliminates the need for a pilot burner that uses gas, improving safety without the risk of gas leakage, and using a combustion burner. Since the structure is simple, maintainability is improved.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view showing the outline of the structure of the combustion burner of the embodiment, and FIG.
3 is a schematic sectional view showing an outline of the structure of a first example of a conventional combustion burner, and FIG. 4 is a schematic sectional view showing an outline of the structure of a second example of a conventional combustion burner. FIG. 3...Fuel spray nozzle, 4...Ignition electrode, 7...
... Spout nozzle, 9... Channel, 10... Ring plate.

Claims (1)

[Scope of utility model registration request] A ring plate is disposed surrounding the jet nozzle in the combustion air flow path in the outer peripheral area of the jet nozzle of the fuel spray nozzle, and an ignition electrode is disposed facing directly downstream of the ring plate. A combustion burner featuring: