随着我国燃煤电厂超低排放改造工作的深入，烟气中可凝结颗粒物（CPM）占比越来越高。作为PM2.5的前体物之一，CPM在大气中的物理化学行为可能与大气环境中PM2.5的爆发式增长存在着密切关系。基于此，本申请提出在超低排放条件下，利用烟雾箱模拟研究CPM在烟囱出口处的转化规律，探索其成核机理；借助环境风洞嵌套烟雾箱的“洞中箱”实验系统，研究烟囱出口一定范围内CPM的变化过程，明确气象因素对其相变及衍生物生成的影响机制；依托回流式环境风洞，研究CPM衍生物在中尺度大气边界层的迁移转化规律和气象条件对PM2.5生成的诱导作用。本研究旨在建立与分析CPM从源排放到大气环境PM2.5转变过程的模型，阐明其对大气环境PM2.5的贡献，完善雾霾形成机理，为大气环境中细颗粒物成分与排放特征的研究提供理论依据。

With the renovation of environmental protection facilities under ultra-low emission standard in China’s coal-fired power plants, the proportion of condensable particulate matter (CPM) in flue gas is becoming higher and higher. As one of PM2.5 precursors, the physical and chemical behaviour of CPM may be closely related to the explosive growth of PM2.5 in the atmosphere. Therefore, the present proposal proposes to study the phase transition mechanism of CPM under the ultra-low emission standards with the simulation experiment using the smoke box, and to clarify the nucleation mechanism. Combined with environmental wind tunnel and smoke box, simulate the phase change process of CPM at the chimney exit with a certain range, and elucidate the influence mechanism of meteorological factors on the phase transition and the formation of derivatives. With the help of the return-flow environmental wind tunnel, study migration and transformation rules of CPM derivatives in the mid-scale atmosphere boundary layer, and clarify the meteorological conditions on the inducement of PM2.5 generation. The research aim of this proposal is to establish and analyze the model of PM2.5 transition from the source emission to the atmospheric environment. The research results will be helpful to ascertain CPM’s contribution to atmospheric PM2.5, improve the formation mechanism of smog, and provide a theoretical basis for studying the composition and emission of fine particulate matter in the atmosphere.