JPH0278811A - Liquid fuel combustion device - Google Patents

Abstract

PURPOSE:To substantially increase a vaporizing surface and to completely vaporize liquid fuel by a method wherein liquid fuel fed through a fuel injection nozzle is caused to flow along a vaporizing surface having a falling gradient in a manner to spread downward. CONSTITUTION:Liquid fuel fed through a fuel injection nozzle 8 to the interior of a vaporizing mixing chamber 9 is brought into contact with a vaporizing surface 38 of the vaporizing mixing chamber 9 heated by a heater 6 for vaporization. Thereafter, the liquid fuel is mixed with primary air through a primary air feed port 27 to produce fuel-air mixture, which is guided through a fuel-air mixture pass port 13 to burner ports 14, 31, and 32 and ignited to form flame F. The vaporizing surface 38 having a falling gradient from a portion positioned facing the fuel injection nozzle 8 is formed on the bottom part of the vaporizing mixing chamber 9. Liquid fuel fed through a fuel injection nozzle 8 is allowed to flow along the vaporizing surface 38 having the falling gradient in a manner to spread downward along, and is vaporized in the middle of the flow by means of heat transferred from the heater 6.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a liquid fuel combustion device that forcibly vaporizes and burns liquid fuel.

[Prior art] As a conventional liquid fuel combustion device of this type,
The technique disclosed in Japanese Patent No. 148820 can be mentioned.

FIG. 3 is a sectional view showing a conventional liquid fuel combustion device.

In the figure, (1) is a cylindrical main body casing with an open upper end, (2) is a combustion chamber formed in the upper part of the main body casing (1), and (3) is a part below the combustion chamber (2). It is a bottomed cylindrical combustor housed in a main casing (1), and consists of an outer cylinder (4) and an inner cylinder (5). (
6) is a heater buried in the bottom of the combustor (3);
7) is a primary air supply port formed in the outer cylinder (4);
8) is a fuel injection nozzle inserted into the secondary air supply port (7). (9) is a vaporization mixing chamber formed as a spiral passage inside the combustor (3), the bottom of which is formed horizontally with each part having the same height, and is connected to the fuel injection nozzle (8). The corresponding part is a vaporization surface (19) that heats and vaporizes the liquid fuel.

(10) is a partition plate that covers the upper surface of the vaporization mixing chamber (9), and a communication hole (11) is formed in a part of the partition plate.

(12) is an outer cylinder (4) above the partition plate (10).
) and the inner cylinder (5).
- A mixture passage port (13) is formed in the center, and a large number of groove-shaped flame holes (14) are formed in the outer periphery.

(15) is a second burner plate disposed above the first burner plate (12), and a large number of slit-shaped flame holes (16) are formed around the entire circumference of the second burner plate. The flame holes (14) and ('16) constitute a combustion section that combusts the air-fuel mixture generated in the vaporization mixing chamber (9>).

Note that (17) is a secondary central air passage formed in the center of the combustor (3), and (18) is a secondary peripheral air passage formed around the outer periphery of the combustor (3).

Next, the operation of the conventional liquid fuel combustion apparatus configured as described above will be explained.

The liquid fuel supplied from the fuel injection nozzle (8) into the vaporization mixing chamber (9) is vaporized on the vaporization surface (19) of the vaporization mixing chamber (9) heated by the heater (6), and the liquid fuel is vaporized and mixed. In the process of swirling along the spiral path of the chamber (9), it is mixed with secondary air from the primary air supply port (7) to form a mixture. This mixture passes through the communication hole (11) of the partition plate (10) and the mixture passage port (13) of the first burner plate (12), is guided to the flame holes (14) and (16), and is ignited (not shown). ignited by means to form a flame (F), which flame (F) is assisted by secondary air supplied from the secondary central air passage (17) and the secondary peripheral air passage (18) to the combustor. (2) is ejected.

[Problems to be solved by the invention] As described above, in the conventional liquid fuel combustion device,
Since the bottom of the vaporization mixing chamber (9>) is formed horizontally with each part at the same height, the liquid fuel supplied from the fuel injection nozzle (8>) is vaporized only on the vaporization surface (19).However, The vaporization surface (located near the fuel injection nozzle (8)
19), heat is removed by vaporization of the liquid fuel and contact with the secondary air, so the temperature of that part locally decreases.

If the temperature of the vaporization surface (1) decreases, the liquid fuel cannot be completely vaporized, and tar, etc. in the liquid fuel will be absorbed by the vaporization surface (19).
becomes easier to adhere to.

When the amount of tar accumulated increases with long-term use, the vaporization surface (19) is covered with a heat insulating layer made of tar, and the vaporization temperature at which the liquid fuel is vaporized is substantially lowered. As a result, the vaporization of the liquid fuel becomes even more insufficient, which may lead to ignition errors in the combustion section.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a liquid fuel combustion device that can suppress the generation of tar components and allow stable operation of a combustor for a long period of time without causing ignition errors.

[Means for Solving the Problems] A liquid fuel combustion device according to the present invention includes a vaporization mixing chamber that heats and vaporizes liquid fuel from a fuel injection nozzle and mixes it with air, and an air-fuel mixture generated in the vaporization mixing chamber. At the bottom of the vaporization mixing chamber, a vaporization surface is formed that slopes downward from a portion corresponding to the fuel injection nozzle.

[Operation] In the present invention, since the liquid fuel supplied from the fuel injection nozzle spreads downward along the downward slope of the vaporization surface and flows, the vaporization surface is substantially enlarged, and the enlarged vaporization surface causes Liquid fuel is completely vaporized.

[Example] The present invention will be explained in detail below.

FIG. 1 is a sectional view of a liquid fuel combustion device according to an embodiment of the present invention, and FIG. 2 is a partially cutaway view of FIG. 1. In addition,
In the drawings, the same reference numerals and symbols as in the conventional example indicate parts that are the same as or correspond to those in the conventional example, and redundant explanation will be omitted here.

In the figure, (21) is an air supply pipe connected to the bottom of the main casing (1), (22) is a support member that accommodates and supports the combustor (3) inside the main casing (1), and (23) is an air supply pipe connected to the bottom of the main casing (1). ) is a secondary peripheral air port formed in the support member (22) so as to communicate with the secondary peripheral air passage (18), and (24) is a combustion port formed in the support member (22) so as to communicate with the secondary central air passage (17). A secondary central air opening formed at the bottom of the vessel (3), (25) a secondary central air swirl plate for swirling the secondary air from the secondary central air passage (17), and (26) - a large air This is a guide cylinder in which a supply port (27) is formed, into which the fuel injection nozzle (8) is inserted.

(28) is a pressure equalizing plate disposed between the partition wall plate (10) and the first burner plate (12), the entire circumference of which passes through the communication hole (11) of the partition plate (10). A large number of adjustment holes (29) are formed to average the pressure of the air-fuel mixture and guide it to the air-fuel mixture passage port (13) of the first burner plate (12).

(30) is a punching plate interposed between the first burner plate (12) and the second burner plate (15), and (31) is a large number of punching plates arranged in an annular manner on the inner side of the second burner plate (15). Inner flame holes arranged in a row, (32) is the second
A large number of outer flame holes are arranged in an annular row on the outer side of the burner plate 1-(15).

(34) is a tapered cylindrical flame throttle member fixed to the inner surface of the main body casing (1) corresponding to the upper end of the combustor (3), and (37) is a flame throttle member (F) from the flame hole (14). ) is used to detect incomplete combustion of the air-fuel mixture.

(38) is a vaporization surface that heats and vaporizes the liquid fuel from the fuel injection nozzle (8). The bottom of the mixing chamber (9) is formed in a downwardly sloping shape.

Next, the operation of the liquid fuel combustion apparatus of this embodiment configured as described above will be explained.

The liquid fuel combustion device of this embodiment operates almost in the same way as the conventional example described above, and is operated from the fuel injection nozzle (8) to the vaporization mixing chamber (9).
) is vaporized by contacting the vaporization surface (38) of the vaporization mixing chamber (9>) heated by the heater (6), and is then vaporized - from the large air supply port (27>). Next, the mixture is mixed with air to form a mixture, and the mixture passes through the communication hole (11) of the partition plate (10) and the mixture passage port (13) of the first burner plate 1 to (12), and then passes through the flame hole (14). ), (3'l)
, (32), and is ignited by an ignition means (not shown) to form a flame (F).

By the way, in the liquid fuel combustion device of this embodiment, a vaporization surface (38> that slopes downward from a portion corresponding to the fuel injection nozzle (8>) is formed at the bottom of the vaporization mixing chamber (9). Therefore, The liquid fuel supplied from the fuel injection nozzle (8) spreads downward along the downwardly sloped vaporization surface (38) and flows, and during the flow, it is vaporized by heat transfer from the heater (6).In other words, it is vaporized. The surface (38) can be substantially enlarged to completely vaporize the liquid fuel on the enlarged vaporization surface (38).

As a result, it is possible to suppress the generation of tar on the vaporization surface (38) and prevent ignition errors.In addition, with long-term use, the vaporization surface near the fuel injection nozzle (8) Even if tar adheres to (38), the vaporization surface (3
8) is formed in an inclined shape, the liquid fuel flows through the tar-attached part and is completely vaporized in the other part of the vaporization surface (38).

[Effects of the Invention] As described above, the liquid fuel combustion device of the present invention includes a vaporization mixing chamber that heats and vaporizes the liquid fuel from the fuel injection nozzle and mixes it with air, and an air-fuel mixture generated in the vaporization mixing chamber. At the bottom of the vaporization mixing chamber, a vaporization surface is formed that slopes downward from the part corresponding to the fuel injection nozzle. As a result, the generation of tar components is suppressed, ignition errors are prevented, and the combustor can operate stably for a long period of time, which is an excellent effect.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a liquid fuel combustion device according to an embodiment of the present invention, FIG. 2 is a partially cutaway view of FIG. 1, and FIG. 3 is a cross-sectional view of a conventional liquid fuel combustion device. In the figure, 8: Fuel injection nozzle 9: Vaporization mixture 14.3
1, 32: Flame hole 38: Evaporation surface. In addition, in the drawings, the same reference numerals and the same reference symbols indicate the same or corresponding parts. Agent: Patent attorney Omiya, geologist, and two others Figure 3

Claims (1)

[Claims] (1) A liquid fuel combustion device comprising: a vaporization mixing chamber that heats and vaporizes liquid fuel from a fuel injection nozzle and mixes it with air; and a combustion section that burns the air-fuel mixture generated in the vaporization mixing chamber; A liquid fuel combustion device characterized in that a vaporization surface is formed at the bottom of a vaporization mixing chamber with a downward slope from a portion corresponding to a fuel injection nozzle.