贫油预混预蒸发（LPP）燃烧是现阶段国内外优先发展的低排放技术，但回火成为限制该燃烧技术进一步发展的瓶颈问题之一，需要发展相应的回火预测模型和规避方法。本项目基于航空发动机低排放燃烧室中横向喷射液雾预混预蒸发特征，对受限空间内液雾两相湍流边界层回火问题开展研究，建立湍流边界层内的流动速度梯度和火焰拉伸率之间的定量关系，在拉伸熄火原理基础上构建液雾湍流边界层回火模型。并采用二元非均相流动反应器中的回火临界条件实验和数值模拟获得的流动速度和燃料浓度分布数据，对回火模型进行验证和改进，形成回火预测及规避设计方法。研究成果可用于预测和评估航空发动机燃烧室回火风险，支持民用航空发动机低排放燃烧室设计方法，使燃烧基础研究成果更好地支撑实际工程应用。

The lean premixed prevaporised (LPP) combustion is the priority in the developing low emissions technologies around the world. However, flashback becomes one of the bottle-neck issues which limit the development of this technology. So the prediction model and control method of flashback need to be developed. Based on the characteristics of premixed prevaporised spray of cross-flow injection in the aero-engine low emissions combustor, the flashback in turbulent boundary layer of confined spray two-phase flow will be researched. Through building up the quantitative relationship between the flow velocity gradient in turbulent boundary layer and the flame stretch rate, the model of flashback in turbulent boundary layer of spray flow could be formulated on the base of the principle of stretched extinction. Then the data of flow velocity and fuel concentration distribution from experiment and numerical simulation on a 2D heterogeneous flow reactor, will be used to validate and modify the flashback model and develop the methodology of prediction and control for the flashback. The research results would be applied to predict and evaluate the flashback risk in aero-engine combustor, and develop the low emissions combustor design methods for civil aero-engines. Additionally, this study could use the fruits of fundamental combustion research to further support the practical engineering applications.