干煤粉加压气化炉对流废热锅炉内多相流场和温度场的数值模拟  

Numerical Simulation on Flow and Temperature Field of Multi-phase Flow in Convective Waste Heat Boiler of Pressurized Coal Gasifiers

作　　者：张传美[1] 金晶[1] 张号[1] 蒋杰[1] 高文静[1] 董振[1] 

机构地区：[1]上海理工大学能源与动力工程学院,上海200093

出　　处：《动力工程学报》2013年第6期424-429,共6页Journal of Chinese Society of Power Engineering

基　　金：上海市教委科研创新重点资助项目(12zz141)

摘　　要：采用数值模拟方法对干煤粉加压气流床对流废热锅炉3段受热面和3圈环隙内合成气的流动和温度分布进行了模拟和分析,其中连续相采用组分输运方程并结合Realizable k-ε湍流模型进行求解,颗粒相采用DPM模型,两相间的相互作用采用双向耦合模型求解,温度场基于离散坐标法及灰气体加权和模型进行求解,高压气体的基本参数采用对比态方法、压力组分修正法和Hottel图表法进行确定.结果表明:由上段受热面至下段受热面,由外圈环隙至内圈环隙,合成气的速度逐渐减小,由于堵板的作用,沿废热锅炉高度方向上速度波峰出现偏移;颗粒质量浓度在合成气入口、上段堵板挡住区域和各段受热面底部较大,需要布置吹灰装置;上段受热面、中段受热面、下段受热面和外侧水冷壁的总传热系数分别为274 W/(m2.K)、243 W/(m2.K)、198 W/(m2.K)和223W/(m2.K).Simulation and analysis were carried out on flow and temperature distribution of syngas in three sections and circles of a convective waste heat boiler for pressurized dry pulverized coal gasifier, in which the gas flow field was calculated by combining species transport equation with Realizable κ-ε turbulence model, while the particle flow field by DPM model. The two-way coupling model was applied to analyze the interaction between gas and particles. Simultaneously, the temperature field was calculated by weigh- ted-sum-of-gray-gases model and DO model, and the basic parameters of high-pressure gases were decided by comparison state method, pressure and species amendment method, and Hottel＇s method. Result show that the velocity of syngas reduces gradually from top to bottom heating surface and from outer to inner an- nular space, and the velocity peak deviates along the height direction due to the action of baffle plates. High concentration of particles appears at the syngas inlet, the bottom of each section and in the area blocked by upper plate, where soot blowers are required. The heat-transfer coefficients of upper, middle and lower heating surface as well as the outer water wall are respectively 274 W/（m^2·K）, 243 W/（m^2·K）, 198 W/（m ^2· K） and 223 W/（m^2·K）.

关 键 词：气化炉 煤气化 对流废热锅炉 多相流 显热回收 数值模拟 

分 类 号：TK229.2[动力工程及工程热物理—动力机械及工程]