粒子浓度对富氧气氛下炉膛内烟气黑度计算的影响
|
摘要
将描述非灰气体辐射特性的统计窄带模型与描述粒子辐射特性的Mie氏理论结合,计算了不同条件下富氧燃烧炉膛内烟气的总黑度.结果表明,由于富氧燃烧中CO2和H2O比例增大,颗粒的存在对燃烧产物黑度计算影响的规律发生变化.在煤粉炉常见的粒子浓度范围内,当行程为5 m时,气体辐射和粒子辐射占同样重要的地位,而行程较大(L>10 m)时,粒子辐射占主导地位,这时可以不考虑气体辐射对辐射换热的影响;当粒子的浓度较小时,可以不考虑粒子的存在对辐射换热的影响.
The total blackness of flue gas in the chamber of oxygen-rich combustion furnace under different conditions is calculated through a statistical narrow-band( SNB) model describing the radiation characteristics of non-ash gases combined with Mie theory which describes the radiation characteristics of particles. Results show that due to the increase of CO_2 and H_2O ratio in the Oxy-coal Combustion,the existence of particle changes the law of the influence of Flue Gas Emissivity of combustion products. In the range of particle concentrations that are common in pulverized coal boiler,when the path length is 5 m,gas radiation and particles radiation occupy and equally important position.;when the path length is large( L > 10 m),the radiation of particles is dominant,and the effect of gas radiation on the heat transfer can't be considered. When the particles concentration is small,the effects of the particle's existence on the radiation heat transfer can be ignored.
The total blackness of flue gas in the chamber of oxygen-rich combustion furnace under different conditions is calculated through a statistical narrow-band( SNB) model describing the radiation characteristics of non-ash gases combined with Mie theory which describes the radiation characteristics of particles. Results show that due to the increase of CO_2 and H_2O ratio in the Oxy-coal Combustion,the existence of particle changes the law of the influence of Flue Gas Emissivity of combustion products. In the range of particle concentrations that are common in pulverized coal boiler,when the path length is 5 m,gas radiation and particles radiation occupy and equally important position.;when the path length is large( L > 10 m),the radiation of particles is dominant,and the effect of gas radiation on the heat transfer can't be considered. When the particles concentration is small,the effects of the particle's existence on the radiation heat transfer can be ignored.
引文
[1]卜昌盛,庄亚明,刘通银,等.煤粉炉微富氧燃烧技术应用研究[J].热能动力工程,2018,33(1):144-150.
[2]韩冬,程伦博,胡海洋,等.富氧燃烧流程建模及系统优化[J].煤炭学报,2013,38(12):2241-2246.
[3]游卓,周志军,胡昕.1 000 MW燃煤锅炉富氧燃烧改造及NOX排放的数值模拟[J].浙江大学学报(理工版),2014(11):2082-2086.
[4]王春波,周慧.小型循环流化床富氧燃烧NOX的生成试验与模拟研究[J].动力工程学报,2010,30(6):420-424.
[5]TOSHIHIKO M,TAKAHIRO M,KENJI K,et al.Development of Hitachi oxy-fuel combustion technologies[J].Energy Procedia,2013,37:1365-1376.
[6]MIKLASZEWSKI EJ,ZHENG Y.Oxy-fuel combustion:laboratory expenriments and pilot scal tests[J].Fuel,2013,104:452-461.
[7]TANIN K,FRANCIS HR,RODRIGO CD,et al.New correlations for the weighted-sum-of-gray-gases-model in oxy-fuel conditions based on HITEMP 2010 database[J].International J Heat Mass Transfer,2012,35:7419-7433.
[8]楚化强,程强,王志超,等.基于窄带模型的烟黑颗粒辐射模型的比较[J].工程热物理学报,2011,32(6):1039-1042.
[9]KLAS A,ROBERT J,STEFAN H,et al.Radiation intensity of lignite-fired oxy-fuel flames[J].Experimental Thermal and Fluid Science,2008,33:67-76.
[10]张艳伟,葛学利,聂宇宏.富氧燃烧锅炉炉膛内烟气辐射特性计算[J].锅炉技术,2016,47(5):51-54.
[2]韩冬,程伦博,胡海洋,等.富氧燃烧流程建模及系统优化[J].煤炭学报,2013,38(12):2241-2246.
[3]游卓,周志军,胡昕.1 000 MW燃煤锅炉富氧燃烧改造及NOX排放的数值模拟[J].浙江大学学报(理工版),2014(11):2082-2086.
[4]王春波,周慧.小型循环流化床富氧燃烧NOX的生成试验与模拟研究[J].动力工程学报,2010,30(6):420-424.
[5]TOSHIHIKO M,TAKAHIRO M,KENJI K,et al.Development of Hitachi oxy-fuel combustion technologies[J].Energy Procedia,2013,37:1365-1376.
[6]MIKLASZEWSKI EJ,ZHENG Y.Oxy-fuel combustion:laboratory expenriments and pilot scal tests[J].Fuel,2013,104:452-461.
[7]TANIN K,FRANCIS HR,RODRIGO CD,et al.New correlations for the weighted-sum-of-gray-gases-model in oxy-fuel conditions based on HITEMP 2010 database[J].International J Heat Mass Transfer,2012,35:7419-7433.
[8]楚化强,程强,王志超,等.基于窄带模型的烟黑颗粒辐射模型的比较[J].工程热物理学报,2011,32(6):1039-1042.
[9]KLAS A,ROBERT J,STEFAN H,et al.Radiation intensity of lignite-fired oxy-fuel flames[J].Experimental Thermal and Fluid Science,2008,33:67-76.
[10]张艳伟,葛学利,聂宇宏.富氧燃烧锅炉炉膛内烟气辐射特性计算[J].锅炉技术,2016,47(5):51-54.