JPH02103302A - combustion device - Google Patents

Abstract

PURPOSE:To obtain an improved flame-holding means so as to reduce the noise and stabilize the combustion irrespective of combustion using a premix or diffused combustion by providing inside a combustion chamber a double-cylinder device combining a nozzle and flame hole which has one or more side-wall holes in the side wall at approximately the central position in the combustion chamber, has inside a cylinder having a length extending beyond the side- wall holes upstream from the forward end, and has at the forward end a resistive member allowing air to pass through and by providing a resistive member between the wall of the combustion chamber and the device combining a nozzle and flame hole at a downstream position from the side-wall holes. CONSTITUTION:A flow of fuel, fed through a fuel pipe 2, spreads as it enters a double-cylinder nozzle-flame hold device 4 and reaches the forward end with a portion flowing through a space between the inner cylinder 5 and the inner wall of the nozzle-flame hole device 4 and the remaining larger portion flowing through the inner cylinder 5. The air for combus tion, which flows between the wall of a combustion chamber 1 and the nozzle-flame hole device 4, is partially diverted by a resistive member 7 through side-wall holes 3 into the space between the inner cylinder 5 and the inner wall of the nozzle-flame hole device 4, forms a fuel-air premix, and then reaches the forward end. As a result, the fuel and the premix are ejected, forming a ring, from a resistive member 6 at the forward end of the nozzle-flame hole device 4. The fuel-air premix is supplied to a flame-staying region (a) formed near the rims of the forward end of the nozzle-flame hole device 4 and forms a firm stabilized flame holder when ignited by means of an igniting device. This constitution is capable of forming a long spiral flame and reducing the noise of the combustion.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to heat source devices such as domestic water heaters, space heaters, and cooking devices.

2. Description of the Related Art As shown in FIGS. 2a and 2b, a conventional combustion apparatus of this type includes swirl vanes 8 for primary and secondary air provided in a combustion air passage 9 in a cylindrical combustion chamber 1. The swirling vanes 8 swirl the combustion air to form a swirling flame near the combustion nozzle 4 at the center of the combustion chamber 1. (For example, Japanese Utility Model Publication No. Sho 63-65'78) Problems to be Solved by the Invention However, the above-mentioned configuration does not have the following problems depending on the method of supplying combustion air. In other words, if premix combustion or combustion is performed with an increased amount of primary air, turbulent, high-load, and noisy combustion will occur, and if combustion is performed with an increased amount of secondary air, tampering is likely to occur, and when the amount of combustion increases, The problem was that unstable combustion was likely to occur in the flame holding area.

The present invention solves these conventional problems, and aims to achieve stable combustion with low noise and enhanced flame stability regardless of premixed diffusion combustion.

Means for Solving the Problems In order to solve the above problems, the combustion device of the present invention has one or a plurality of side wall holes in the side wall approximately in the center of the combustion chamber, and a hole is formed inside the side wall from the tip to the side wall hole. A double cylindrical nozzle/flame hole having a cylinder having a length extending to the upstream side and having a breathable resistor (for example, wire mesh, ceramics, etc.) at the tip, and the nozzle downstream from the side wall hole. A resistor (e.g. wire mesh, ceramics, etc.) is placed between the flame hole and the combustion chamber.
It is equipped with the following.

Operation The combustion device of the present invention has the above-mentioned configuration, and while the pressurized fuel spreads through the fuel pipe and inside the double cylindrical nozzle/flame hole, a portion of the fuel flows between the inner wall of the nozzle/flame hole and the inner cylinder. Most of the rest flows inside the inner cylinder and is ejected from the tip into the combustion chamber.

At this time, the air flow for combustion supplied into the combustion chamber is partially flowed from the side wall hole above the nozzle/flame hole to between the inner wall of the nozzle/flame hole and the inner cylinder due to the resistor installed between the nozzle/flame hole and the combustion chamber. By the time the flow reaches the tip, a premixture is formed and flows out from the tip resistor, and the rest flows downstream between the combustion chamber inner wall and the nozzle/flame hole. This premixed air is then supplied to a stagnation region formed near the rim at the tip of the nozzle/flame hole. As a result, after ignition by the ignition source, a strong and stable flame holding is formed in the stagnation region near the rim, resulting in stable combustion with low noise.

Embodiment Hereinafter, an embodiment of the present invention will be explained based on the attached drawings. In FIG. Combustion air is supplied while forming a swirling flow. (In other cases, the fuel is supplied without forming a swirling flow.) A fuel pipe 2 is provided on the substantially solid axis in the combustion chamber 1 to form a tip having one or more side wall holes 3 in the side wall. A thick cylindrical nozzle and flame hole 4 is provided. Inside this nozzle/flame hole 4, an inner cylinder 5 having a cylinder length extending from the tip to the upstream side of the side wall hole 3 is provided on a substantially concentric circle, and the nozzle/flame hole 4 and the inner cylinder 5 are provided.
It has a double structure with a resistor 6 having air permeability provided at the tip. Furthermore, a resistor 7 is provided between the nozzle/flame hole 4 and the combustion chamber 1 downstream of the side wall hole 3.

In the above configuration, while the fuel spreads through the fuel pipe 2 and inside the nozzle/flame hole 4 on the double cylinder, a part of the fuel flows between the inner wall of the nozzle/flame hole 4 and the inner cylinder 5, and most of the other part flows inside the nozzle/flame hole 4. It flows inside the cylinder 5 and reaches the tip. On the other hand, a part of the combustion air flowing between the nozzle/flame hole 4 and the combustion chamber 1 flows through the side wall hole 3 between the inner wall of the nozzle/flame hole 4 and the inner cylinder 5 due to the resistor 7, and is premixed. Forms Qi and reaches the tip. As a result, the fuel/premixture is ejected in an annular shape from the resistor 6 at the tip of the nozzle/flame hole 4. Then, the premixture is supplied to the stagnation area (a) formed near the rim at the tip of the nozzle/flame hole 4, and the ignition source (not shown)
By this, a strong and stable flame holding can be formed after ignition, and a low-noise, swirling long flame can be formed.

Effects of the Invention As described above, the present invention provides an inner cylinder having one or more side wall holes in the side wall approximately in the middle of the combustion chamber, and having a cylinder length extending from the tip to the upstream side of the side wall hole. A combustion device comprising: a double cylindrical nozzle/flame hole having a gas permeable resistor at its tip; and a resistor between the nozzle/flame hole and the combustion chamber downstream of the side wall hole. Therefore, stable combustion and noise reduction can be achieved by strengthening flame stability.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of a combustion device according to an embodiment of the present invention, and FIG. 2 is a sectional view of a conventional combustion device. 1... Combustion chamber, 3... Side wall hole, 4...
... Nozzle and flame hole, 5 ... Inner cylinder, 6 ...
...Resistor, T...Resistor. Name of agent: Patent attorney Shigetaka Awano (1 person) Figure α

Claims (1)

[Claims] A double cylindrical shape having at least one side wall hole in the side wall, an inner cylinder having the same length from the tip to the upstream side of the side wall hole, and a resistor provided at the tip, approximately in the center of the combustion chamber. A combustion device comprising: a nozzle/flame hole, and a resistor between the nozzle/flame hole and the combustion chamber downstream of the side wall hole.