JPH02103305A - Combustion device - Google Patents

Abstract

PURPOSE:To improve a device for supplying hot water in radiant heat-absorbing property so as to enhance the thermal efficiency and make the device slim in structure by applying an infrared material having a high absorptivity in the infrared region to the inner wall of a combustion tube by coating or otherwise by forming, by providing at a distance upstream from a nozzle a gyratory device by means of which the air from a blower is sent in spiraling form into the combustion tube, and by providing a long outer tube which functions as a water tube for passing water through. CONSTITUTION:A flame is formed at the contact surface between gas and spiraling air. By virtue of the spiral movement the air forms the contact surface in a uniform, little turbulent state and is supplied in a thin uniform flow lengthwise along a combustion tube 2. As a result, a flame 11 which has a high luminance and is very long and slender is formed in the middle part of the combustion tube 2. Despite the length, the combustion generates no soot, and since a long flame 11 is formed in the combustion tube 2, a long heating surface, varying little in temperature, is formed. The radiant heat from the long luminous flame is collected at a high absorptivity by a infrared-absorptive material 4 on the inner side of the combustion tube so that an improvement in thermal efficiency and uniformity of the heat can be achieved. When a water tap is turned ON and the water is passed through a water tube 3 simultaneously with the ignition, the water is heated almost evenly at all points along the long combustion tube 2.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a household combustor, and is intended for use in small water heaters and the like.

BACKGROUND ART Conventionally, this type of combustor has been a small gas water heater as shown in FIG. 2 and a water heater as shown in FIG. 3.

The former forms a flame 15 in a wide combustion chamber called a drum 14, and a heat exchanger 16 with fins placed on top of the flame 15.
It heats water using a gas water heater, which requires a large capacity like the gas water heaters used in many home kitchens. Also,
The latter is a so-called radiant tube 17 used in commercial water heaters inserted into water, and this example shows a double-pipe radiant tube, with a short flame that does not cause soot at the tip of the nozzle 18. 19 is made and the water is heated. In this case, the flame must be short to avoid sooting, and there is a means to speed up the diffusion of fuel and air, which generates heat near the nozzle, causing local heating of the tube. In addition, the diameter of the pipe is also thicker, and in practical use it is more than 50 mm.

Problems to be Solved by the Invention In the above devices, the equipment itself has a large volume, and it is impossible to install a thin and slim water heater in a narrow space, for example, in accordance with water pipes. . Even radiant tubes need to be thick to obtain the necessary amount of combustion, and need to be about the same size as a small household water heater. In addition, in this case, the smaller the diameter of the tube, the more likely the heat will be concentrated near the nozzle outlet as described above, and the more likely it will be localized heating.

The present invention solves these conventional problems, and eliminates local heating by forming a long flame and obtaining a long heating surface with small temperature difference, which was previously considered impossible. The provision of an outer high-absorbing material improves the absorption of radiant heat and increases thermal efficiency, and by flowing water along this long flame, a combustor that can be used as a slim water heater is provided.

Means for Solving the Problems In order to solve the above problems, the combustor of the present invention uses a long inner tube separated from each other and formed into a double tube shape as a combustion tube, and the inner wall of this combustion tube is provided with an infrared light. An infrared material having a high absorption rate is coated or formed, a combustion nozzle is provided at one end of the combustion tube, a blower is provided upstream of the combustion tube, and a swirl is provided upstream at a distance from the nozzle. The body provides a swirling flow to the air from the blower and supplies it to the combustion tube, and the outer tube of the long tube is configured as a water tube through which water passes.

Operation With the above configuration, the present invention supplies swirled air from the upstream side of the nozzle so as to follow the flow of fuel ejected from the nozzle. It is thought that this swirling air uniformizes the diffusion surface with the fuel by swirling, forming a thin mixing surface with little turbulence, stretching the flow of the fuel and creating a very long flame with strong yellow flame inside the combustion tube. to form a long heating surface with high heat uniformity. By coating or configuring an infrared absorbing material on the inner surface of this combustion tube, and configuring the water tubes through which water passes around the outer periphery of this combustion tube in a concentric circle, heat transfer is uniformized and a slim water heater with high heating efficiency is created. becomes.

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. 1st
In the figure, numeral 1 is a long tube separated into two passages in a double-tube shape, and is composed of an inner tube 2 and an outer tube 3. This inner tube 2 forms a combustion tube, and its inner periphery is made of, for example, transition element oxide ceramics (exlMnO, FezO, Cub, Coo, etc.).
A highly infrared absorbing material 4 such as ceramic) is coated, vapor-deposited, or made of the material itself. Its length and diameter are determined by the aim and amount of combustion, but experiments have shown that it is possible to make it 10 mm or more in diameter and 100 cm or more in length. For example, a flame length of 100 cm is obtained using a tube with a diameter of 16 mm. A fuel nozzle 5 for ejecting fuel is inserted concentrically into one end of the combustion tube (inner tube) 2, and its tip forms a planar flame-holding surface 7 around the nozzle hole 6. Reference numeral 8 denotes a rotating body such as a swirling blade that swirls the combustion air supplied from a blower device 9 such as a fan, and is provided upstream of the nozzle 5 and concentrically with the nozzle 5 .

10 is a fuel pipe that sends fuel to the nozzle 5.

Numeral 11 is a long flame formed concentrically with the combustion tube 2, and 12 is an exhaust port at the outlet end of the combustion tube 2. A distance is provided between the nozzle 5 and the rotating body 8 so that the swirling flow along the combustion tube 2 is uniformly applied to the stream downstream from the nozzle 5.

The outer tube 3 is a double tube concentrically with the combustion tube 2, and is a water tube that is separated from the combustion tube 2 and serves as a water flow path, and has a length between the combustion tube and the passage. , One end is connected to a water pipe (not shown) and the other end is connected to a hot water faucet (not shown). Reference numeral 13 denotes a heat insulator surrounding the water tube (outer tube) 3. In the above configuration, fuel gas is ejected from the nozzle 5, and air is supplied from the blower 9 as swirling air via the swirling body 8 from the upstream side of the nozzle 5 so as to be in contact with the flow of the fuel gas, and is ignited and burned. At this time, a flame is formed at the contact surface between the gas and the swirling air, but due to the swirling, the air forms a uniform and less turbulent contact surface, and is also supplied thinly and uniformly in the length direction of the combustion tube 2. As a result, a very long and thin flame 11 with high brightness is formed in the tube 2. In our experiment, for example, the diameter is 16m+n,
In a combustion tube with a length of 100 cm, the length of the flame 11 is 40
-100cm or more was obtained. Even with such a length, no soot is generated, and a long flame 11 is formed within the combustion tube 2, thereby forming a long heating surface with a small temperature difference. Furthermore, the radiant heat from this long luminous flame is recovered at a high absorption rate by the infrared absorbing material on the inner surface of the combustion tube, contributing to improved thermal efficiency and uniformity of heat. Therefore, if water is allowed to flow from the tap into the water pipe 3 at the same time as the ignition, the water will be heated almost uniformly over the entire long combustion pipe 2. The hot water is then supplied from the faucet. Note that the strength of the swirling is desirably such that it does not disturb the gas jet flow.

Effects of the Invention As described above, the combustor of the present invention makes it possible to form a long flame with high brightness in a thin tube, which was unimaginable in the past, and to create a long heating surface with small temperature difference. It can be configured as a slim pipe-shaped water heater, and its long flame eliminates localized heating, making it a durable device, and it is also a heat source device that can be used for heating, drying, oven heating, etc. It also becomes. Incidentally, if the pipe with a diameter of 16 mm is used, it is possible to configure the combustor as a water heater with a diameter of about 30 mm.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of a main part of a combustor according to an embodiment of the present invention, and Fig. 2 is a combustor conventionally used in a home kitchen.
Long pipe (double pipe), 2... Combustion pipe (inner pipe), 3.
...Water tube (outer tube), 4...Infrared material, 5
... Fuelable nozzle, 8 ... Rotating structure, 9 ...
...Blower device.

Claims (1)

[Claims] The inner tube of a long tube separated from each other and formed into a double tube shape is used as a combustion tube, and the inner wall of this combustion tube is coated or formed with an infrared material that has a high absorption rate in the infrared region, and one end of this combustion tube is A combustion nozzle is provided facing the combustion nozzle, a blower is provided on the upstream side of the combustion pipe, and a swirling body provided upstream at a distance from the nozzle gives a swirling flow to the air from the blower and supplies the air to the combustion pipe. In addition, the combustor is configured such that the outer tube of the long tube is a water tube through which water passes.