摘要
生物质燃料燃烧后所产生的烟气中含有大量的水蒸气,在锅炉尾部添加冷凝换热器回收冷凝热可以有效提高系统热效率。选用的生物质燃料烟气中水蒸气的体积分数为27.9%,基于Mixture模型并选用Lee模型作为冷凝传质模型对尾部烟气凝结的传热传质特性进行了数值模拟研究。假设流动为稳态,湍流模型采用标准k-ε模型,求解选用Simple算法,研究了烟气侧不同入口流速下(1~4 m/s)温度场、流场及液态水体积分数的变化规律,对翅片管换热器的表面传热系数及换热量进行了对比分析。计算结果表明,随着入口流速的增加,烟气出口温度逐渐升高,壁面凝结速率不断增大,而冷凝水量逐渐减少,同时翅片管换热器的表面传热系数及换热量逐渐增加。
The biomass fuel combustion smoke contains large amounts of water vapor.Adding at the end of the boiler condensing heat exchanger recovery condensing heat can effectively improve system efficiency.The chosen biomass fuel vapor in flue gas volume fraction is 27.9%.Based on the Mixture model and Lee model is chosen as the condensation mass transfer model for the tail flue gas condensation heat and mass transfer characteristics of the numerical simulation study.The temperature field,flow field and volume fraction of liquid water at different inlet flow rates(1~4 m/s)on the flue gas side are studied.The surface heat transfer coefficient and heat transfer of finned tube heat exchanger are compared and analyzed.The calculation results show that with the increase of inlet flow rate,the flue gas outlet temperature increases gradually,the wall condensation rate increases continuously,and the condensation water decreases gradually,and the surface heat transfer coefficient and heat transfer of finned tube heat exchanger increase gradually.
作者
高波
阴继翔
李涛
陈颢
GAO Bo;YIN Jixiang;LI Tao;CHEN Hao(School of Electrical and Power Engineering,Taiyuan University of Technology,Taiyuan,Shanxi 030024,China)
出处
《上海电力大学学报》
CAS
2022年第1期1-8,共8页
Journal of Shanghai University of Electric Power
基金
国家自然科学基金(51476108)
山西省科技重大专项(MD2016-02)。
关键词
Lee模型
烟气凝结
传热传质
温度场
凝结速率
Lee model
condensation of flue gas
heat and mass transfer
temperature field
condensation rate
