微尺度下氢氧预混合气催化燃烧的研究  

Study on Catalytic Combustion of Premixed Hydrogen and Oxygen in the Micro-scale

作　　者：潘剑锋[1] 范宝伟[1] 吴庆瑞[1] 李晓春[1] 唐爱坤[1] 薛宏 

机构地区：[1]江苏大学能源与动力工程学院,镇江212013 [2]美国加州工业大学机械工程系

出　　处：《机械工程学报》2011年第24期111-116,共6页Journal of Mechanical Engineering

基　　金：国家自然科学基金(50706016);江苏省基础研究计划(BK2008245);江苏省高校优势学科建设工程;江苏大学'拔尖人才培养工程'资助项目

摘　　要：基于空间气相和表面催化的详细化学反应机理,应用计算流体动力学软件对亚毫米燃烧器内的氢氧预混合燃烧进行模拟,在对催化燃烧模型进行试验验证的基础上,讨论不同反应模型的燃烧特性以及壁面材料和进口流速等对催化燃烧反应的影响。模拟结果显示,表面催化反应会使壁面相邻位置空间气体内的OH质量分数降低,对该催化壁面临近区域的气相反应有所抑制;壁面催化反应与空间气相反应耦合进行时,燃烧效率可达到最大值;进口速度对出口排气温度的影响要大于对外壁面最高温度的影响,进口速度过高会导致燃烧效率降低;燃烧器材料的选择也对催化燃烧有着重要的影响,采用热导率较小的材料时,燃烧器壁面存在较高的温度梯度,燃烧器外壁面温度也较高,而采用热导率较大的材料时,壁面对进口端的气体预热作用增强,高温燃烧区域向入口端移动。Catalytic combustion of hydrogen and oxygen mixture inside a sub-millimeter micro combustor is numerically investigated by using the commercial computational fluid dynamics（CFD） code which based detailed gas phase and surface catalytic chemical reaction mechanisms.Combustion characteristics for different reaction models and the influence of wall materials and inlet velocity on catalytic combustion reaction are discussed on the basis of experimental verification.The computational results show that the surface catalytic combustion restrains the gas phase combustion by reducing the mass fraction of OH at adjacent position.Combustion efficiency can reach maximum value when coupling the surface catalytic combustion and the gas phase combustion.Inlet velocity will take more influence onto the temperature of ouelet exhaust than the temperature of outerwall,and the too higher velocity will lead to the reducing of combustion efficiency.Wall materials also have important influence on catalytic combustion of hydrogen and oxygen,there are large temperature gradient and temperature value in the outer wall of combustor when materials with small heat conductivity are used.The high temperature combustion zone moves to the entrance side because of the increase of the heat exchange form the combustor wall to the mixed gas near the entrance when materials with large heat conductivity are used.

关 键 词：催化燃烧 亚毫米 微尺度 数值模拟 

分 类 号：TK50[动力工程及工程热物理—热能工程]