Guide: Question: What is the flame center of a condensing boiler? Answer: After the fuel enters the furnace of the condensing boiler, on the one hand, the flame temperature is continuously increased due to the heat generated by the combustion of the fuel, and on the other hand, due to the heat absorption of the boiler water wall

　　Question: What is the flame center of a condensing boiler?

　　Answer: After the fuel enters the furnace of the condensing boiler, on the one hand, the heat generated by the combustion of the fuel increases the flame temperature, and on the other hand, the heat absorption of the boiler water wall reduces the flame temperature. When the heat generated by the fuel combustion is greater than the heat absorption of the water wall, the flame temperature rises; when the heat generated by the fuel combustion is equal to the heat absorption of the water wall, the flame temperature reaches the highest. The highest temperature in the furnace of the condensing boiler is called the flame center. The height of the flame center is not fixed, but changes with the change of boiler operating conditions. For example, when the burner is divided into two rows and the upper row throws more, the flame center moves upward, otherwise it moves downward.

　　Q: What is the flame center? How does the height of the flame center affect the heat transfer in the furnace?

　　Answer: After the fire is on, due to the gradual development of combustion, the heat released by the combustion is greater than the heat transfer, so the temperature of the flue gas continues to rise, thus forming a rapid burning and higher temperature area. The most heat is released in this area. This area is usually called the flame center (or combustion center).

　　Under a certain excess air coefficient, if the flame center moves up, the total heat exchange in the furnace will decrease, and the flue gas temperature at the furnace outlet will increase; if the flame center moves down, the heat exchange in the furnace will increase and the flue gas at the furnace outlet will increase. Temperature drop.

　　Q: Why should the flame center be adjusted?

　　Answer: During the operation of the condensing boiler, if the flame center in the furnace is deviated, the flame fullness of the entire furnace will deteriorate. On the one hand, there is a large smoke temperature difference between the front, rear, left, and right of the furnace, which causes uneven heating of the water wall, which may disrupt the normal water circulation. On the other hand, the flue gas temperature difference between the left and right sides of the furnace outlet is caused, which makes the temperature on the furnace outlet side higher, causing the superheater and other heating surfaces on this side to overheat the tube to burst. Therefore, during operation, pay attention to adjusting the flame center position to make it located The center of the furnace.

　　Q: How to adjust the flame center during operation?

　　Answer: For burners arranged at four corners, they should run symmetrically in the same row, without missing corners, and have uniform output. And try to keep the air velocity and load at the outlet of each combustor uniform. Or change the flame center position by changing the tilt angle of the swing burner or the ratio of the upper and lower secondary air.