航空发动机中心分级燃烧室流场特性与燃烧机理研究

This project focus on the flow field and combustion characteristics and combustion stability in the central staged combustor of an aero-engine, which is a critical technology problem. By applying theory analysis, experimental study and numerical simulation, the flow field characteristics in the central staged combustor were measured by PIV and simulated by LES (large eddy simulation). The structure of flow field in the combustor was obtained, and the effects of the cyclone structure and the fuel ratio of primary and pilot on the flow field structure were presented. The combustion process and combustion stability of this combustor were experimental measured, the characteristics of the outlet temperature field and emissions concentration field, the boundary and gas oil ratio of lean blowout were obtained. Through establishing the combustion and lean blowout mechanisms of the central staged combustor coupled recirculation zone, the characteristics of combustion, emissions and lean blowout were simulated, the effects of the cyclone structure and the fuel ratio of primary and pilot on the combustion and emissions characteristics and combustion stability of this combustor were analyzed, and the effect mechanism of the flow field characteristics on the combustion and emissions characteristics and combustion stability was presented. This research will present original results and provide the scientific basis and technical support for the structure design and preformance optimization of the new high efficiency and low pollution combustor.

项目围绕航空发动机中心分级燃烧室的流场特性、燃烧特性与燃烧稳定性这一关键科技问题，采用理论分析、实验研究和数值计算相结合的方法，对中心分级燃烧室的流场特性进行PIV实验测量与大涡模拟，获得该燃烧室内的流场结构，阐明旋流器结构、值班级与主燃级燃油比例分配等对该燃烧室流场结构的影响规律；对该燃烧室的燃烧过程与燃烧稳定性进行实验测量，获得燃烧室出口温度场与排放物浓度场的分布特性、贫油熄火边界与贫油熄火油气比；建立中心分级燃烧室耦合回流区的燃烧机理与贫油熄火机理，对该燃烧室的燃烧特性、排放特性及贫油熄火特性进行数值计算，分析旋流器结构、值班级与主燃级燃油分配比例等对该燃烧室的燃烧特性、燃烧稳定性与主要排放物生成规律的影响，阐明流场特性对燃烧特性、排放特性与燃烧稳定性的影响机理。该项研究必将提出原创性成果，为新型高效低污染燃烧室的结构设计与性能优化提供理论依据与技术支持。

近年来，为了使航空发动机更加具有竞争力，航空发动机的推进效率、总增压比和涡轮进口温度在不断提高，从而使航空发动机的燃烧温度、强度及NOx排放也在大幅提高。由于飞机飞行高度接近平流层，航空发动机的NOx排放对臭氧层的破坏远高于地面燃机，飞机尾气也是高空大气污染物的唯一来源。为此国际民航组织曾四次修改民用航空发动机污染排放标准，相继颁布了CAEP1、CAEP2、CAEP4 和CAEP6，对NOx排放的控制越来越严格。以压缩比为36的发动机为例，与CAEP2的NOx排放标准相比，CAEP4的NOx排放标准降低了12%，CAEP6的NOx排放标准更是降低了21%。因此，低污染燃烧室和低污染燃烧技术已经成为现代高性能航空发动机的重要标志之一。.中心分级燃烧室结构非常复杂，燃烧室内流场特性、燃烧机理也与常规燃烧室区别较大，国外相关研究尚处于起步阶段。同时，由于相关技术的国外引入限制，目前对中心分级燃烧室的流场特性、燃烧特性及燃烧稳定性尚不明了。项目围绕航空发动机中心分级燃烧室的流场特性、燃烧特性与燃烧稳定性这一关键科技问题，采用理论分析、实验研究和数值计算相结合的方法，对中心分级燃烧室的流场特性进行PIV实验测量与大涡模拟，获得该燃烧室内的流场结构，阐明旋流器结构、值班级与主燃级燃油比例分配等对该燃烧室流场结构的影响规律；对该燃烧室的燃烧过程与燃烧稳定性进行实验测量，获得燃烧室出口温度场与排放物浓度场的分布特性、贫油熄火边界与贫油熄火油气比；建立中心分级燃烧室耦合回流区的燃烧机理与贫油熄火机理，对该燃烧室的燃烧特性、排放特性及贫油熄火特性进行数值计算，分析旋流器结构、值班级与主燃级燃油分配比例等对该燃烧室的燃烧特性、燃烧稳定性与主要排放物生成规律的影响，阐明流场特性对燃烧特性、排放特性与燃烧稳定性的影响机理。该项研究必将提出原创性成果，为新型高效低污染燃烧室的结构设计与性能优化提供理论依据与技术支持。项目资助发表文章20篇，其中SCI-4篇，EI-11篇，中文核心-5篇，发明专利-4项。培养硕士生6名，其中5名已取得硕士学位，1名在读。项目投入经费83万，支出80万，各项支出基本与预算相符，剩余经费计划用于本项目后续支出。