Impact of Air Leakage from Furnace Bottom on Flame Style and Exhaust Flue Gas Temperature

doi:10.11930/j.issn.1004-9649.2016.05.091.06

Abstract

Abstract: To uncover the reasons for the substantial exhaust flue gas temperature rise without much flue gas temperature change at the air heater inlet when cold air leaks from the furnace bottom, the computational fluid dynamics simulation is conducted to study the variation patterns of the flame style with Fluent software. The results show that the bottom air leakage has very few impacts on the flame style in the area above the combustor zone and the flame center. However, if the bottom air leakage reaches as much as 10% of the total air volume, the flame temperature at the furnace outlet will increase by 15.7 ℃. Based on the heat balance principle of the air heater, two relational expressions are derived presenting the exhaust flue gas temperature rise due to the air reduction in the air heater caused by bottom air leakage, which explains why the exhaust flue gas temperature rises significantly while the flue gas temperature remains almost the same at the air heater inlet in the event of furnace bottom air leakage. The study results can provide reference for relevant work in this field.

Key words: thermal power plant, boiler, furnace bottom, air leakage, flame style, exhaust flue gas temperature

CLC Number:

ZHAO Zhenning, LI Yuanyuan, ZHANG Qingfeng, ZHAO Zhenzhou. Impact of Air Leakage from Furnace Bottom on Flame Style and Exhaust Flue Gas Temperature[J]. Electric Power, 2016, 49(5): 91-96.

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URL: https://www.electricpower.com.cn/EN/10.11930/j.issn.1004-9649.2016.05.091.06

https://www.electricpower.com.cn/EN/Y2016/V49/I5/91

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