旋流波瓣燃烧器冷/热态流场及富氢合成气燃烧特性

The designs of swirl lobe combustors are presented to improve the flashback of premixed combustion and reduce the emission of diffusion combustion. Both experiments and the numerical simulations will be carry out to investigate the characteristics of cold/ fired flow field and combustion of hydrogen-enriched syngas on novel low swirl combustors. The core component of the combustor is a lobe-swirler which can play the role of mixing and swirling the syngas at the same time. The syngas is swirled in oblique channels between the adjacent crests and troughs when flows through both sides of the lobe swirler, and mixed in the downstream. This combustor can be used in the mode of diffusion combustion or premixed combustion. It also can be in the transition state between the two combustion modes. The cold flow field downstream of the lobe-swirler will be measured by a seven-hole pressure probe in a low velocity and large scale wind tunnel. The cold/ fired flow field of the lobe-swirler will be measured by the LDV and PIV in the combustion experiment platform. The relationship between flow characteristic, combustion characteristic and the geometric parameters of the combustors will be summarized. This project will also focus on the flashback characteristics and the emission characteristics of lean premixed combustion of the hydrogen-enriched fuel. The emission characteristics of diffusion combustion will also be studied. And finally, numerical simulations will be used to give more detail insights into the flow field and flame. Investigations will focus on characteristics of mixing, swirling and developing of complicated vortex structures downstream of the lobe-swirler. Another key scientific problem is the coupling mechanisms of combustion products, temperature field and velocity field.

为拓宽富氢合成气预混燃烧的回火裕度、降低扩散燃烧的污染物排放，提出了旋流波瓣燃烧器设计方法，针对冷热态流场特性以及富氢合成气燃烧特性开展实验和数值模拟研究。该燃烧器核心部件为具有掺混和旋流双重作用的波瓣旋流器，流经其两侧的气体在相邻波峰和波谷间的斜流通道作用下旋转，并在波瓣旋流器下游进行掺混。该新型燃烧器可扩散燃烧也可预混燃烧，还可在这两种燃烧模式之间过渡。在低速大尺度风洞上利用七孔探针测试波瓣旋流器下游的冷态流场；在燃烧实验台利用激光多普勒测速仪和粒子图像测速仪测试波瓣旋流器下游的冷态和热态流场。总结旋流波瓣燃烧器几何参数与流动特性和燃烧特性之间的关系。重点关注富氢燃料的回火特性、污染物排放特性。通过数值模拟获得更加全面细致的流动和燃烧图谱。围绕波瓣旋流器下游反应物掺混和旋流特性及复杂涡系结构的演化规律；旋流波瓣燃烧器燃烧产物、温度场、速度场之间的耦合作用机制这两个关键科学问题开展研究。

为了强化燃烧反应物之间的掺混、拓宽预混燃烧的稳定工作区间、降低扩散燃烧的污染物排放，提出了旋流波瓣燃烧器的设计方法，针对冷热态流场特性以及燃烧特性开展了实验和数值模拟研究。该燃烧器核心部件为具有掺混和旋流双重作用的波瓣旋流器，流经其两侧的气体在相邻波峰和波谷之间的斜流通道作用下旋转，并在波瓣旋流器下游进行掺混。该新型燃烧器可以扩散燃烧也可以预混燃烧，还可以在这两种燃烧模式之间过渡。在低速大尺度风洞上利用七孔压力探针测试了波瓣旋流器下游的冷态流场；在燃烧实验台利用激光多普勒测速仪和粒子图像测速仪测试了波瓣旋流器下游的冷态和热态流场。建立了波瓣旋流器的设计方法；总结了旋流波瓣燃烧器几何参数与流动特性和燃烧特性之间的关系；获得该新型喷嘴的回火特性、污染物排放特性；并通过数值模拟获得全面细致的流动和燃烧图谱；揭示了波瓣旋流器下游反应物掺混和旋流特性及复杂涡系结构的演化规律。本研究有助于深入认识波瓣旋流器下游的流场结构和燃烧特性，为波瓣旋流器的工程应用提供理论和技术支撑，有助于新型结构紧凑的高效清洁燃烧喷嘴的研发。参加国际会议一次(ASME Turbo Expo 2017)，并在大会上介绍了相关研究成果。在工程热物理年会上以板报形式介绍了研究进展。在本项目资助下撰写稿件十篇，其中8篇稿件已经发表，获得发明专利授权10项。