【作者】 李姮；

【导师】 程乐鸣； 施正伦；

【作者基本信息】 浙江大学 ， 工程热物理， 2006， 硕士

【摘要】 论文结合国家“西气东送”，以开发燃气高效清洁燃烧为背景，重点研究多孔介质燃烧装置中的气固温度分布及其传热特性。 气体燃料在多孔介质中的燃烧技术在很多方面具有优越性，将它应用于天然气的高效低污染燃烧，不仅能缓解气体燃料燃烧领域污染物排放严重的问题，而且能配合“西气东输”工程，加大天然气在沿海地区的利用力度，加速天然气的民用化，具有学术上和工程上的双重价值和意义。 多孔介质是固体骨架和流体组成的一类多相复合介质。多孔介质燃烧技术是预混气体混合物在一种耐高温、导热性能好的特殊多孔介质材料中的燃烧过程。由于多孔基体的存在，预混气体在流经多孔介质的同时进行燃烧，气体在多孔介质孔隙内部旋涡、分流和汇合，剧烈扰动，因此燃料在多孔介质中的预混燃烧是一个包含导热、对流和热辐射三种换热方式互相耦合的复杂过程。 试验在对原有多孔介质燃烧装置改造的基础上，通过在多孔介质燃烧装置的不同位置设置石英玻璃观测窗口，实现了燃烧室的可视化，采用精确定位的非接触式红外测温仪对多孔介质燃烧区气孔和固体网格温度进行测量，获取多孔介质中的气固两相温度分布场。以此分析燃烧区温度分布及其变化规律，研究多孔介质结构参数、预混气体流速、燃气当量比、燃烧强度等参数对燃烧室气固温度分布的影响，揭示均匀与渐变型孔隙气体与多孔介质网格架之间的传热特性。更多还原

【Abstract】 The thesis takes aim at understanding the temperature distribution of gas/solid grids and heat transfer characteristics in a porous media combustor.Porous media is formed with solid frame of complex structure. The premixed gas swirls, splits, merges and burns in the pores of the porous media. The combustion is a complex process involving conduction, convection and radiation together.To measure the temperature of gas/solid grids in the porous media, several silica windows were set along the height at different position around the combustor. A non-contact infrared thermo-scope was used to measure the temperature of gas/solid grids. Further more, the gas/solid temperature profiles of the porous media were obtained.The experiments investigated the effect of equivalent ratio, combustion rate, superficial gas velocity, size of pore and porous media structure on the gas/solid grids temperature profiles in the combustor. The result showed there was a temperature difference between the pore gas and the solid grids. The temperature of solid grids is about 60~80°C lower than that of gas in the pore at most cases. Based on the experimental results, the heat transfer characteristics of the porous media combustor was analyzed and a volume heat transfer coefficient was estimated by a simply computation.更多还原