摘要
基于两相流的欧拉壁膜模型和组分输运模型耦合的方法,针对1种调峰型的气化炉壳侧内部进行建模,研究了烟气垂直向上流动时,螺旋盘管管壁外表面的相变行为及液膜的形成过程和分布情况。计算结果表明:当烟气通过管道外壁面时,烟气中水蒸气在管道外壁发生相变。首先在底部盘管壁面发生凝结形成液膜,随着时间的推进,凝结过程持续进行。底部盘管表面先凝结形成的液膜最厚,上部盘管表面后冷凝形成的液膜逐渐变薄,在内圈盘管形成的液膜厚度要比外圈厚。烟气进入换热区域直至盘管外壁全部覆盖液膜用时2.4 s,液膜厚度达2.57×10^(-5) m,各测量点烟气温度与实验测值误差在5%以内,排烟温度310~330 K,含水量为6.2%,为新型气化炉结构的优化设计提供理论依据。
Based on the coupling method of Eulerian Wall Film and Species Transport Model for two-phase flow,a model was established for the shell side of a peak loading gasifier.The phase transition behavior and the formation process and distribution of liquid film on the outer surface of spirally coiled tube wall when the flue gas flows vertically upward were studied.The results show that when the flue gas passes through the outer wall of the pipe,the water vapor in the flue gas changes phase on the outer wall of the pipe.Firstly,condensation occurs on the wall of the bottom coil to form a liquid film,and the condensation process continues with time.The film formed on the surface of the bottom coil is thicker than that on the surface of the upper coil.The film formed on the inner coil is thicker than that on the outer coil.It takes 2.4 seconds from the flue gas entering to the outer wall of the coil fully covered with the liquid film.At this time,the thickness of the liquid film reaches 2.57×10^(-5) m.The error of the flue gas temperature at different measuring points between the calculation and the experimental measurement is less than 5%.The temperature of the flue gas is about 310~330 K,and the water content is 6.2%.The heat transfer mechanism data of the integrated gasifier are in good agreement with the simulation results,which can provide theoretical basis and reference for the optimization design of gasifier structure.
作者
郭韵
陈昊
樊俊杰
GUO Yun;CHEN Hao;FAN Junjie(School of Mechanical and Automotive Engineering,Shanghai University of Engineering Science,Shanghai 201620,China;School of Environment and Architecture,University of Shanghai for Science and Technology,Shanghai 200093,China)
出处
《锅炉技术》
北大核心
2021年第3期1-7,共7页
Boiler Technology
基金
国家自然科学基金项目(51606116)
上海市科委基金项目(19195810800)。
关键词
调峰型气化炉
欧拉壁膜模型
两相流
液膜
相变
peak loading gasifier
eulerian wall film
two-phase flow
liquid film
phase change
