排气管形式对排气管阻力及燃烧性能的影响  

Effect of Combustion Products Evacuation Duct Form on Resistance of Combustion Products Evacuation Duct and Combustion Performance

作　　者：吕昕宇 刘文博 刘贵川[1,2] 周伟业 张梦婷[1,2] LYU Xinyu;LIU Wenbo;LIU Guichuan;ZHOU Weiye;ZHANG Mengting

机构地区：[1]中国市政工程华北设计研究总院有限公司城市燃气热力研究院,天津300384 [2]国家燃气用具质量监督检验中心,天津300384

出　　处：《煤气与热力》2020年第6期25-31,J0043,共8页Gas & Heat

基　　金：天津市科技计划(19YFZCCG00550)。

摘　　要：燃气采暖热水炉的排气管形式(包括排气管长度、挡风圈内直径、弯头数量)影响排气管阻力,从而影响燃气采暖热水炉的燃烧性能。通过实验测试不同排气管形式对排气管阻力及燃烧性能的影响,介绍实验装置及方法,对实验数据进行分析。实验分别在不同排气管长度、挡风圈内直径、90°弯头数量的工况下进行,记录相应工况下的引风机出口压力、排气管出口压力、NOx体积分数等参数,计算排气管阻力、烟气体积流量、燃气采暖热水炉的热效率、过剩空气系数。研究表明:排气管阻力与挡风圈内直径之间呈非线性负相关,挡风圈内直径越小,排气管阻力增长速度越快。对于内直径60 mm的搪瓷排气管,1个90°弯头的阻力约为2.5 m排气管的阻力。热效率、NOx体积分数随着排气管阻力的增加近似呈线性增加,过剩空气系数、烟气体积流量随着排气管阻力的增加近似呈线性减小。安装合适长度的给排气管和合适数量的弯头时,可以与原配给排气管加装相应的挡风圈时的排气管阻力、烟气体积流量达到基本相同,燃烧工况也较为相近。The combustion products evacuation duct form of gas-fired heating and hot water combi-boilers(including the length of combustion products evacuation duct,the inner diameter of wind shielding ring and the number of elbows)affects the resistance of combustion products evacuation duct,thereby affecting the combustion performance of gas-fired heating and hot water combi-boilers.The influence of different combustion products evacuation duct forms on the resistance of combustion products evacuation duct and the combustion performance was tested through experiments.The experimental devices and methods are introduced,and the experimental data were analyzed.The experiments were performed under conditions of different lengths of combustion products evacuation ducts,different inner diameters of wind shielding rings and different numbers of 90°elbows.The parameters such as the outlet pressure of the induced draft fan,the outlet pressure of combustion products evacuation duct and the NO x volume fraction under the corresponding working conditions were recorded.The resistance of combustion products evacuation duct,the flue gas volume flow rate,the thermal efficiency of gas-fired heating and hot water combi-boilers and the excess air coefficient were calculated.The experimental results show that there is a non-linear positive correlation between the resistance of combustion products evacuation duct and the inner diameter of wind shielding ring.The smaller the inner diameter of wind shielding ring,the faster the resistance of combustion products evacuation duct increases.For enameled combustion products evacuation duct with inner diameter of 60 mm,the resistance of a 90°elbow is approximately equal to the resistance of combustion products evacuation duct of 2.5 m.The thermal efficiency and NO x volume fraction increase linearly with the increase of the combustion products evacuation duct resistance.The excess air coefficient and flue gas volume flow rate decrease linearly with the increase of the combustion products evacuation

关 键 词：燃气采暖热水炉 排气管形式 阻力 烟气体积流量 热效率 燃烧性能 

分 类 号：TU996.7[建筑科学—供热、供燃气、通风及空调工程]