JPH0439506A - Liquid fuel burner - Google Patents

Abstract

PURPOSE:To promote the atomization of the fuel by arranging in a pressurized spraying section a multihole body in which a vibration section and air supply section communicate. CONSTITUTION:In the pressurized spraying section 3 a multihole body 9 which communicates with a compressor 7 and air supply pipe 8 and a vibration section 10 which consists of a piezoelectric vibration element are arranged. With this arrangement even when the combustion quantity is at minimum, it is possible to have minute air bubbles dissolved in the fuel, and whey they are jetted out to the outside, the atmospheric pressure falls and the minute dissolved bubbles in the fuel explode by the volume expansion and it is possible to promote the atomization of the fuel.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a liquid fuel combustion device, and particularly to one used for domestic hot water supply and space heating.

BACKGROUND OF THE INVENTION In recent years, there has been an increasing demand for wider variable range of combustion amount, lower noise, and smaller size of equipment for burning petroleum and other liquid fuels.

Conventionally, the burner section of this type of pressure spray type liquid fuel combustion equipment has generally been as shown in FIG. This will be explained below with reference to FIG.

As shown in FIG. 3, a fuel tank 21 and a fuel pump 2
2 and the pressure IIji mist nozzle 23 communicate with each other through PmW24 to form a fuel supply path, and the pressure spray nozzle 23
is arranged inside the air passage 25 and extends into the combustion chamber 26. Further, the air passage 25 communicates with a ventilation fan 27, and a swirling blade 2 is provided at the opening end of the air passage 25 to the combustion chamber 26.
8 is placed. In the above configuration, the fuel tank 21
The supplied fuel is pressurized to a set pressure by the fuel pump 22, supplied to the pressure spray nozzle 23, and is ejected from the pressure spray nozzle 23. and is sprayed into the combustion chamber 26. On the other hand, combustion air is supplied from a blower fan 27, passes through a blower passage 25, and is supplied to a combustion chamber 26. At this time, a swirling airflow is formed by the swirling vane 28, and the pressure spray nozzle 2
A combustion reaction occurs with the fuel sprayed from step 3, forming a flame.

Problems to be Solved by the Invention In such a conventional liquid fuel combustion device, the flame length becomes large due to the large particle size of the fuel spray ejected from the pressure spray nozzle 23, making it difficult to downsize the device. Furthermore, combustion noise was generated by the popping sound when fuel particles were rapidly boiled by the flame, so it was not possible to reduce the combustion noise. Further, since the atomization of the fuel when ejected from the pressure spray nozzle 23 is covered by the kinetic energy of the ejected fluid, if the ejection flow velocity becomes smaller, the kinetic energy also becomes smaller, making it impossible to atomize the fuel sufficiently. In other words, the jet flow velocity is determined by the amount of fuel burned, so when the combustion amount decreases, the jet flow velocity also decreases and the kinetic energy also decreases, so the fuel spray particle size increases and combustion is poor, making it impossible to vary the combustion amount. .

The present invention has been made to solve the above-mentioned problems, and aims to make a liquid fuel combustion device more compact and less noisy, and to widen the variable range of combustion amount.

Means for Solving the Problems In order to achieve the above objects, the present invention provides a fuel supply section that supplies liquid fuel, a fuel supply pipe that communicates this fuel supply section and a pressure spray section, and an air supply section that supplies air. comprising a supply section and an air supply pipe communicating the air supply section and the porous body,
The porous body and the vibrating part are arranged inside the pressure spray part, and the pressure spray part looks into the combustion chamber.

Effect of the present invention With the above-described configuration, microbubbles generated from the porous body are generated inside the fuel ejected from the pressure spraying section, and are further reduced by the vibration waves generated in the vibrating section and propagating within the liquid fuel. It is dissolved in the
Since the atmospheric pressure is reduced by being ejected to the outside, the dissolved microbubbles rapidly expand in volume and burst, thereby promoting atomization.

EXAMPLE Hereinafter, a liquid fuel combustion apparatus according to an example of the present invention will be described with reference to FIGS. 1 and 2.

As shown in the figure, the fuel tank 1, fuel bomb 2, and pressure spray section 3 communicate with each other through a fuel supply pipe 4 to form a fuel supply path, and the pressure spray section 3 is connected to the inside of the air blow path 5. It is arranged and looks into the combustion chamber 6. Inside the pressure spray section 3, there is a porous body 9 that communicates with the compressor 7 through an air supply pipe 8.
A vibrating section 10 made of a piezoelectric vibrator is also arranged.

Further, the air passage 5 communicates with an air blowing fan 11 , and a swirling blade 12 is arranged at an open end of the air passage 5 to the combustion chamber 6 .

In the above configuration, the fuel supplied from the fuel tank 1 is pressurized to a set pressure by the fuel pump 2 and supplied to the pressure spray section 3, while the air pressurized to the set pressure by the compressor 7 is Generated from the body 9 as microbubbles,
Further, the ultrasonic vibrations generated by the vibrating section 10 made of a piezoelectric vibrator and propagating within the fuel form even smaller microbubbles and dissolve within the fuel of the pressure spray section 3. The fuel is ejected from the pressure spray section 3 and is atomized by the shear force generated by the relative velocity with the surrounding air, and the dissolved microbubbles inside the fuel particles rapidly expand in volume and burst as the atmospheric pressure decreases. , atomization is promoted and sprayed into the combustion chamber 6. On the other hand, combustion air is supplied from the blower fan 11 and is supplied to the combustion chamber 6 through the blower path 5 . At this time, a swirling airflow is formed by the swirling vanes 12, which undergoes a combustion reaction with the fuel sprayed from the pressure spray section 3 to form a flame.

In this way, according to the liquid fuel combustion device of this embodiment, the dissolved microbubbles in the fuel supplied from the porous body 9 are increased so that a sufficient ejection flow velocity can be obtained even when the combustion amount is the minimum. As a result, the volumetric flow rate can be increased, a sufficient jetting flow velocity can be maintained, and the combustion variable width can be widened.
The microbubbles generated from the porous body 9 are in a dissolved state due to ultrasonic vibrations generated by the vibrating part 10 made of a piezoelectric vibrator, and when they are ejected to the outside, the atmospheric pressure decreases and the volume expands rapidly. Since the fuel ruptures, it is possible to promote the atomization of the fuel, and therefore it is possible to obtain fuel spray with a small particle size over a wide combustion variable range. Also,
The microbubbles supplied from the porous body 9 dissolved inside the fuel particles act as air pre-mixed with fuel for accelerated combustion, so that accelerated combustion can be achieved and the combustion rate can be made higher than that of diffusive combustion. I can do it. Therefore,
The flame length is short for a wide variable combustion range, allowing for smaller equipment, and the spray particle diameter is small, reducing combustion noise caused by bursting sounds when fuel particles are rapidly boiled by the flame. It is possible to reduce the noise level of the equipment.

Effects of the Invention As is clear from the description of the embodiments above, according to the liquid fuel combustion apparatus of the present invention, a porous body communicating with the vibrating part and the air supply part is disposed inside the pressure spray part, so that the combustion Even when the amount is minimal, it is possible to dissolve microbubbles inside the fuel, and when it is ejected to the outside, the atmospheric pressure decreases and the dissolved microbubbles in the fuel burst due to volume expansion, promoting atomization of the fuel. . Therefore, it is possible to obtain a spray with small fuel particle diameter over a wide combustion variable range.Furthermore, the microbubbles dissolved in the fuel act as air mixed with the fuel in advance, resulting in accelerated combustion, resulting in a short and quiet flame length. It can form a flame, provide a small and low-noise device with a wide combustion range.

[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 cross-sectional view of a pressure spray part of the liquid fuel combustion device,
FIG. 3 is a sectional view of a conventional liquid fuel combustion device. Vibration part. Name of agent: Patent attorney Shigetaka Awano and one other person.

Claims (1)

[Claims] A fuel supply section that supplies liquid fuel, a fuel supply pipe that communicates the fuel supply section and the pressure spray section, an air supply section that supplies air, and an air supply pipe that communicates the air supply section and the porous body. A liquid fuel combustion device comprising: the porous body and the vibrating section disposed inside the pressure spray section, and the pressure spray section looking into a combustion chamber.