JPS636578Y2 - - Google Patents

Description

[Detailed explanation of the invention] (Field of industrial application) This invention is an in-tube combustion system that achieves stable in-tube combustion with extremely good flame holding performance, and achieves quiet, high-load combustion without vibration. This relates to burners.

(Prior art and problems) In many conventional tube combustion burners, a fuel tube is installed inside the tube and the air is simply swirled for combustion. Therefore, a swirling flame is formed only in the center of the tube, and the flame is The temperature near the burner did not rise and the temperature distribution became uneven, making it impossible to achieve high-load combustion. In addition, in the case where a short flame-holding tube is installed and the gas is simply swirled, the flame may settle in the short flame-holding tube, causing red heat and burnout of the short flame-holding tube, narrowing the stable combustion range, and causing combustion vibration. This method has the disadvantage that it is easy to generate air leakage, and that low excess air cannot be achieved. The present invention is intended to solve these drawbacks, and will be detailed below with reference to the drawings.

(Means for solving the problem) Reference numeral 1 denotes a fuel pipe inserted into an air pipe 2. At the tip of this fuel pipe 1, a primary air hole 3 is formed in a tapered part 7, and a primary air hole 3 is formed on the outer periphery. Secondary air swirl vane 4
A cylindrical flame-holding tube 5 provided with a flame-holding tube 5 is installed so as to be in contact with the inner wall of the air tube 2. Inside the fuel pipe at the base of the cylindrical flame-holding tube 5, a flame-holding rod 6 having a spiral groove at the same turning angle and in the same direction as the secondary air swirling vane 4 is installed. . The swirling vane 4 may be constituted by a round bar as shown in the figure.

(Function) Now, when fuel gas is supplied to the fuel pipe 1, the fuel gas becomes a swirling flow from the flame holding rod 6 and flows into the tapered part 7.
flowing along the inner wall of the On the other hand, the combustion air supplied into the air pipe 2 is divided into primary air and secondary air at a predetermined ratio.
The air flowing out from the cylindrical flame holding tube 5 flows along the parallel portions of the cylindrical flame holding tube 5 while forming an air layer on the inner wall of the cylindrical flame holding tube 5, preventing red heat of the cylindrical flame holding tube 5 and preventing the flame holding rod from becoming red. It mixes with gas in a recirculation region formed downstream of the center of the flame holding rod 6, and is ignited by an ignition rod 8 provided at the center of the flame holding rod 6, forming a swirling flame 9. Further, the secondary air flowing out while swirling from the swirling vanes 4 contacts and mixes well with the swirling flame 9 to form a large swirling flame and secondary combustion is performed. At this time, the secondary air swirl vanes 4 and the flame stabilizing rods 6
As mentioned above, since they are configured at the same swirling angle and in the swirling direction, there is no sudden change in the flow, and the transition from primary combustion to secondary combustion is smooth, and at the same time the cylindrical shape is maintained. The temperature near the flame tube 5 also rises sufficiently, the temperature distribution becomes good, and low excess combustion can be achieved in the overall combustion. Furthermore, a recirculation area is formed in the rim portion 10 at the tip of the cylindrical flame holding tube 1, as shown by the arrow in the figure, which further strengthens flame holding and stabilizes combustion over a wide range. However, together with the swirling flow flame 9, it becomes a continuous ignition source for combustion within the tube, and stable combustion can be maintained.

(Effects of the invention) Since the present invention is as described above, the temperature in the vicinity of the cylindrical flame-holding tube rises sufficiently, the temperature distribution is good, and at the same time, there is no red heat of the cylindrical flame-holding tube, and there is sufficient temperature. Due to the flame-holding effect, the stable combustion range is wide, so it has the excellent effect of achieving low excess air and high-load combustion in the pipe. Furthermore, by changing the mixing ratio of primary air and secondary air, the same effect can be obtained with any fuel, and at the same time, it is an excellent device that can be used for premix combustion and premix combustion.

[Brief explanation of the drawing]

The figure shows one embodiment, and FIG.
The cross-sectional explanatory drawing and FIG. 2 are front views. Code 1...Fuel pipe, 2...Air pipe, 3...Primary air hole, 4...Secondary air swirl vane, 5...Cylindrical flame holding tube, 6...Flame holding rod, 7...Tapered part , 8...
Ignition rod, 9... swirling flame, 10... rim section.

Claims (1)

[Scope of utility model registration request] At the tip of the fuel tube inserted into the air tube, a cylindrical flame-holding tube with a primary air hole formed in the tapered part and a secondary air swirling vane on the outer periphery is installed so as to be in contact with the inner wall of the air tube. At the same time, in the fuel pipe at the base of the cylindrical flame stabilizing tube, a flame stabilizing rod having a spiral groove provided at the same swirling angle and in the same swirling direction as the secondary air swirling vane is installed. In-tube combustion burner.