喷嘴参数对超临界水热燃烧特性影响的模拟  

Simulation of effect of nozzle parameters on supercritical hydrothermal combustion characteristics

作　　者：王芝安 兰忠[1] 马学虎[1] WANG Zhian;LAN Zhong;MA Xuehu(Liaoning Key Laboratory of Clean Utilization of Chemical Resource,School of Chemical Engineering,Dalian University of Technology,Dalian 116024,Liaoning,China)

机构地区：[1]大连理工大学化工学院,辽宁省化工资源清洁利用重点实验室,辽宁大连116024

出　　处：《化工学报》2024年第6期2190-2200,共11页CIESC Journal

基　　金：国家自然科学基金项目(51836002)。

摘　　要：反应器喷嘴的作用是维持水热火焰在复杂流场中保持稳定。建立内预热式蒸腾壁反应器(IPTWR)内甲醇超临界水热燃烧过程计算流体力学模型,分析了喷嘴的材料热物性和结构参数对进料混合特性及火焰结构的影响规律。结果表明,喷嘴材料传热特性的提高使水热火焰朝高温和广域的方向发展;氧气-辅热混合段直径由18 mm减小到14 mm,反应器轴向温度峰值由954.84 K升高到981.60 K,火焰位置向远端移动;随着喷嘴缩进深度减小,水热火焰逐渐向喷嘴出口聚拢,表现为火焰收缩现象。在此喷嘴结构参数范围内小直径的短氧气-辅热混合流道有助于水热火焰的温度升高和聚拢稳定。结果可为内预热式蒸腾壁反应器的喷嘴设计提供理论指导。The role of reactor nozzle is to maintain the stability of the hydrothermal flame in a complex flow field.A computational fluid dynamics model of the supercritical hydrothermal combustion process of methanol in an internally preheated transpiration wall reactor(IPTWR)was developed,and the effects of material thermophysical properties and structural parameters of the nozzle on the feed mixing characteristics and flame structure were analyzed.The results show that the improvement of the heat transfer characteristics of the nozzle material makes the hydrothermal flame move toward high temperature and wide area;the diameter of the oxygen-assisted heat mixing section decreases from 18 mm to 14 mm,the peak axial temperature of the reactor increases from 954.84 K to 981.60 K,and the flame position moves toward the distal end;with the decrease of the indentation depth of the nozzle,the hydrothermal flame is gradually converged toward the nozzle outlet,which is manifested as a phenomenon of flame contraction.In this nozzle structure parameter range,the short oxygen-assisted heat mixing flow path with small diameter helps the hydrothermal flame temperature increase and gathering stabilization.Theoretical guidance is provided for the nozzle design of the internal preheated transpiration wall reactor.

关 键 词：喷嘴 反应器 超临界水 水热火焰 计算流体力学 

分 类 号：TK16[动力工程及工程热物理—热能工程]