JPH0810043B2 - Combustion device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a combustion apparatus for burning a premixed gas fuel and air on the surface of a flame hole cylinder.

[Prior Art] FIG. 3 is a sectional view showing a liquid fuel combustion apparatus as a conventional combustion apparatus disclosed in, for example, Japanese Patent Application Laid-Open No. 61-17817. In FIG. 3, (1) shows a burner body. Vaporization tube, (2) is a heater cast in the vaporization tube (1),
(3) is a mixing plate having a throttle portion provided on the upper part of the vaporizing cylinder (1), (4) is a nozzle, and the vaporizing cylinder (so that the tip of the needle (6) is located at the center of the tip (5)) Connected to 1), (7) is a flame hole cylinder made of a cylindrical wire mesh, which is crimped around the bottom of the mixing plate (3), and the second end face of the flame hole cylinder (7). The entire circumference of the upper part is closed by seam welding with the closure cap (30). Also, the entire lower circumference as the first end face of the flame hole cylinder (7) is the mixing plate (3).
And the inside is in communication with the vaporization cylinder (1). Inside the flame hole cylinder (7), at the upper part of the outlet of the mixing plate (3), straightening plates (8), (9) for rectifying the premixed gas flowing from the mixing plate (3) to the flame hole cylinder (7). ) Is provided. The obstruction cap (30) has a taper-shaped protruding portion extending inside the flame hole tubular body (7), and a cooling pipe (10) as a cooling means is inserted therein. Also the cooling pipe (1
The other end of (0) is opened toward the blower fan (20) with its end being expanded like a bell mouth.

In addition, the louver (1
1) is provided.

 Next, the operation will be described.

The vaporization cylinder (1) is previously heated to 200-300 ° C by the heater (2).
When preheated, the air is vaporized from the nozzle (4) in the cylinder (1).
The fuel is also sprayed in a mist form from the needle (6) along with it, vaporized in the vaporization cylinder (1) to become gaseous fuel, and mixed with air to form a premixed gas with a uniform concentration and mixed. It jets into the flame hole cylinder (7) in the normal direction of the straightening vanes (8) and (9) through the flat plate (3), the straightening vanes (8) and (9). The jetted air-fuel mixture flows along the blocking cap (30) and almost uniformly jets from the flame hole cylinder (7) to form a flame. Although the temperature of the flame hole cylinder (7) rises due to the flame, the heat transferred to the closing cap (30) by heat conduction and radiant heat transfer is blown from the blower fan (20) through the cooling pipe (10) for cooling. Since the air is forcibly cooled, the temperature of the closing cap (30) is lowered, and the temperature of the flame hole cylinder (7) is also lowered.

[Problems to be Solved by the Invention] Although the conventional combustion device is configured as described above, in such a combustion device, if the combustion amount is too large, the cooling effect of the flame hole cylinder is insufficient. The temperature of the flame hole cylinder rises and becomes higher than the heat resistant temperature, or a so-called flashback phenomenon occurs in which the flame burns inside the flame hole cylinder. on the other hand,
If the amount of combustion is made too small, the flame temperature lowers and carbon monoxide and odors are easily generated.

Therefore, there was a problem that the combustion change width (TDR), which is the ratio of the maximum combustion amount to the minimum combustion amount, could not be increased.

The present invention has been made to solve the above problems, and an object of the present invention is to obtain a combustion device that improves the cooling efficiency of the flame hole cylinder, thereby improving the combustion change width (TDR). .

[Means for Solving the Problems] A combustion apparatus according to a first aspect of the present invention includes a burner body for premixing gaseous fuel and air, a flame hole tube body having a first end surface communicating with the burner body, A closing cap provided on the second end face of the flame hole cylinder, having a tapered protrusion on the inside of the flame hole cylinder, and having cooling means for cooling the protrusion from the inside with air; An uneven portion is provided on the surface of the protruding portion.

A combustion apparatus according to a second aspect of the present invention is a burner body for premixing gaseous fuel and air, a flame hole cylinder whose first end surface communicates with the burner body, and a second flame hole cylinder body.
A closure cap provided on the end face of the flame hole cylinder inside the flame hole cylinder and having a cooling means for cooling the projection with air from the inside. It is a spherical surface.

[Operation] In the combustion device of the first aspect of the present invention, by providing the protrusions and depressions on the surface of the protrusion of the closure cap, the surface area of the protrusion is increased, and the heat transfer with the refrigerant supplied by the cooling means is improved. The cooling efficiency for the flame hole cylinder is improved.

Further, in the combustion apparatus of the second invention, the outer tip of the protruding portion of the closing cap is formed into a split spherical surface,
The distribution of the premixed air inside the flame hole cylinder can be made uniform, the flame distribution can be made uniform, and the size of the protruding portion is extended, so that the cooling efficiency for the flame hole cylinder is increased. Also contribute to the improvement of.

[Embodiment] In each of the embodiments, a liquid fuel combustion apparatus will be described as a combustion apparatus as in the conventional example.

A liquid fuel combustion apparatus (hereinafter referred to as a combustion apparatus) according to an embodiment of the combustion apparatus according to the first invention will be described below.
This will be described with reference to the drawings. FIG. 1 is an explanatory view showing a cross section of a main structure of a combustion apparatus according to an embodiment of the first invention. In FIG. 1, reference numerals (7) and (10) indicate the same or corresponding portions as those shown in FIG. 3, and the description thereof will be omitted.

In FIG. 1, (31) is a closing cap, but unlike the conventional example shown in FIG. 3, a concavo-convex portion (32) is formed on the surface of a tapered protrusion (hereinafter appropriately referred to as a tapered surface). )
To increase the surface area.

(33) is a rectifying plate, and this rectifying plate (33) is connected to the closing cap (31) by a support fitting (34) in order to increase the strength of the flame hole tubular body (7) and the like. By connecting and fixing the closing cap (31) and the rectifying plate (33) with the support fitting (34), the closing cap (31) and the cooling pipe (10) which were conventionally only applied to the flame hole tubular body (7). The stress caused by the above can be dispersed in the flow straightening plate (33), which contributes to extending the life of the flame hole cylinder (7) by preventing deformation.
(35) is a mixing plate to which the current plate (33) is fixed.

In the case of a combustion device with such a main structure, during combustion operation,
Although the closing cap (31) is forcibly cooled from the inner surface side by the cooling air flowing out from the lower end of the cooling pipe (10), the concavo-convex portion (32) is provided on the tapered surface of the closing cap (31) to provide the surface area of the tapered surface. The cooling efficiency is improved as compared with the conventional example, and it is possible to prevent an excessive temperature rise of the flame hole cylinder (7), which in turn extends the life of the flame hole cylinder (7). The maximum combustion amount can be increased as well as being extended.

Next, an embodiment of the combustion apparatus according to the second invention will be described with reference to FIG.

FIG. 2 is an explanatory view showing a cross section of the main structure of the combustion apparatus according to the embodiment of the second invention. In FIG. 2, reference numerals (1), (7), and (10) indicate the same or corresponding portions as those shown in FIG. 1 or 3, and the description thereof will be omitted as appropriate. In FIG. 2, (41) is a closing cap, but unlike the conventional cap and the first invention, the outer tip of the protrusion is a split spherical tip (42) of split spherical surface, It is arranged close to the current plate (43). Reference numeral (44) is a support fitting for connecting and fixing the closing cap (41) and the current plate (43), and (45) is a mixing plate to which the current plate (43) is fixed.

In the case of the combustion device having such a main structure, the vaporization cylinder (1)
The premixture flowing from the inside of the flame hole cylinder (7) through the mixing plate (45) and the flow straightening plate (43) is along the smooth surface of the split spherical tip (42) of the closing cap (41). Since the premixture inside the flame hole cylinder (7) has a uniform distribution, the flow is smooth with little turbulence, and the flame distribution on the surface of the flame hole cylinder (7) is made even more uniform. In addition, since the size of the protrusion is extended by making the tip of the protrusion a split spherical surface, the cooling efficiency is improved. As a result, the life of the flame hole cylinder (7) can be extended and the combustion change width can be increased.

In addition, in the above-mentioned embodiments of the invention, it is also possible to apply a heat-resistant paint having a high emissivity, such as Okitsumo, on the surface of the protruding portion of the closing cap ((31) or (41)), In this case, it is possible to improve the radiant heat transfer from the flame hole cylinder (7) and obtain a combustion device with better cooling efficiency.

Further, in the embodiments of the above-mentioned inventions, the case where the liquid fuel is vaporized as the fuel has been described, but other than that, the vaporization of the solid fuel or the gas fuel from the beginning can be applied. ， Has the same effect.

[Advantages of the Invention] As described above, in the combustion device of the first aspect of the present invention, the surface area of the protrusion is increased by providing the projections and depressions on the surface of the tapered protrusion of the closure cap, so that the cooling of the closure cap is increased. Efficiency is improved.

As a result, it is possible to prevent an excessive temperature rise in the flame hole cylinder, suppress the occurrence of a flashback phenomenon, and extend the life of the flame hole cylinder.

Further, as described above, in the combustion apparatus of the second invention, the outer tip of the tapered projection of the closing cap is formed into a split spherical surface, so that the premixed gas flowing inside the flame hole cylinder body is split spherical surface. It spreads uniformly along the outer tip of the cylinder into the inside of the flame hole cylinder, and its flow is smooth with little turbulence. As a result, the flame distribution on the surface of the flame hole cylinder can be made even more uniform. It is possible to realize a stable combustion state. Further, since the outer tip portion of the protruding portion of the flame hole cylinder is extended as a split spherical surface, the dimension becomes longer, so that the cooling efficiency is improved. As a result, it is possible to prevent an excessive temperature rise in the flame hole cylinder, suppress the occurrence of a flashback phenomenon, and extend the life of the flame hole cylinder.

[Brief description of drawings]

FIG. 1 is an explanatory view showing a cross section of a main part structure of a combustion apparatus according to an embodiment of the first invention, and FIG. 2 is an explanatory view showing a cross section of a main part structure of a combustion apparatus according to an embodiment of the second invention. FIG. 3 and FIG. 3 are explanatory views showing a conventional liquid fuel combustion device. In the figure, (1) is a vaporization cylinder, (7) is a flame hole cylinder, and (1
(0) is a cooling pipe, (31) and (41) are closure caps, (3)
2) is an uneven portion, and (42) is a split spherical tip. In each figure, the same reference numerals indicate the same or corresponding parts.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Teruo Sugimoto, Inventor 8-1-1 Tsukaguchihonmachi, Amagasaki-shi, Hyogo Sanryo Electric Co., Ltd. Central Research Laboratory (72) Minoru Sato 8-chome, Tsukaguchihonmachi, Amagasaki-shi, Hyogo No. 1 Sanryo Electric Co., Ltd. Central Research Laboratory

Claims (2)

[Claims] 1. A burner body for premixing gaseous fuel and air, a flame hole cylinder whose first end face communicates with the burner body, and a flame hole provided on the second end face of this flame hole cylinder body. Combustion characterized by comprising a closed cap having a tapered protrusion on the inside of the cylinder and having a cooling means for cooling the protrusion from the inside with air, and providing an uneven portion on the surface of the protrusion. apparatus. 2. A burner body for premixing gaseous fuel and air, a flame hole cylinder whose first end face communicates with the burner body, and a flame hole provided on the second end face of this flame hole cylinder body. It is provided with a closing cap having a tapered protrusion on the inside of the cylinder and having a cooling means for cooling the protrusion from the inside with air, and the outer tip of the protrusion is split spherical. Characteristic combustion device.