How should this sentence in the standard be understood?
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The last edit to this post was made by xyfeng007 on 2021-6-1 at 15:06. There is a sentence in the GBT 19839 Standard for General Technical Requirements of Industrial Fuel and Gas Burners that says so. "When the static pressure at the burner outlet reaches 1.1 times the furnace pressure of the associated furnace, the air volume at the burner outlet should be sufficient to ensure normal combustion at the maximum flow rate within the range permitted for burner adjustment. " I’m new to this standard and have little exposure to the relevant content. I also hope to receive plenty of guidance from the enthusiastic friends on this forum. How should this sentence be understood? Are they requirements for the minimum sizing and maximum resistance of the burner? Understanding 1: Assuming a positive pressure inside the furnace, when the combustion air fan supplies air at the rate required for fuel combustion at maximum flow, should the static pressure at the burner outlet be no less than 1.1 times the furnace pressure? Understanding 2: Assuming a positive pressure inside the furnace, when the combustion air fan blows air at the volume required for fuel combustion at maximum flow rate, is the static pressure at the burner outlet not higher than 1.1 times the furnace pressure? Or is this sentence meant to emphasize something else?
It is the parameter used during type testing of burners: when the pressure at the outlet, as measured by a pressure gauge, is 1.1 times the maximum pressure inside the furnace, the air flow rate can reach the designed value
Following this line of reasoning, can it be understood that if the pressure at the outlet is 1.1 times the maximum pressure in the furnace, then if the actual air flow rate is greater than the designed flow rate, does that indicate that the burner has better performance?
Give it a boost so the post doesn’t get buried! !
This post was last edited by Forgetting = Forgetting on 2021-6-2 at 15:46. Within the load regulation range, when the maximum fuel flow rate is considered (taking into account a +5% flow variation) and the static pressure at the outlet is 1.1 times the specified value, the air volume at the burner outlet ensures complete combustion of the fuel under these conditions, thereby preventing pollution and waste
The static pressure at the burner outlet reaches 1.1 times the furnace pressure of the associated furnace. What kind of extreme operating condition does this requirement regarding the burner outlet pressure correspond to? Are there any special considerations? Why is the standard set at 1.1, rather than 1.05 times, or 1.2 times, 1.5 times? If we consider full combustion, does a higher value indicate better burner performance?
The last edit to this post was made by Forgetting = Forgetting on 2021-6-4 at 11:07. The relationship between the maximum flow rate corresponding to the outlet pressure and the combustion exhaust gases is most directly reflected in the furnace pressure and temperature distribution. There are also standards governing the structural design of the furnace chamber as well as the temperature of the exhaust gases at the outlet. A higher value indicates a stronger fuel supply capacity on the part of the burner; this requires the furnace chamber to withstand greater transient pressures, as well as more space and a better-designed structure to facilitate the distribution of the flow fields.
If it is below 1.0 times, this issue need not be considered; if it is 1.1 times, then it is necessary to ensure that the air flow can meet the amount of air required for the maximum gas flow. The main problem is that at 1.1 times, certain conditions arise – specifically low furnace pressure and high gas outlet pressure – which can lead to incomplete combustion. Therefore, it is important to adjust the air volume so that it meets the requirements for the maximum gas flow. Please refer to the subsequent explanations for more details.
Is there an explanatory text for this standard? The version I downloaded doesn’t seem to have any explanatory text. I’ll look for it online again to see if there’s something wrong with my version.