正丁醚高压着火及其发动机低温燃烧的基础研究

含氧生物燃料正丁醚可通过木质素制备，是一种极具前景的新型替代燃料。本项目通过试验和仿真手段，针对正丁醚在近发动机工作条件下的着火过程，以及其在发动机新型燃烧模式下的燃烧和排放特性开展系统研究。进而阐明正丁醚在高压条件下的均质气相及输运/化学耦合作用的着火特性及机理，解析正丁醚高压直喷着火过程中的物理/化学着火延迟及其与运行参数间的关联，明确废气再循环中稀释/活性成分对正丁醚直喷着火特性的影响规律和作用机制，揭示正丁醚发动机在低温预混合燃烧模式下的着火、放热和排放特性，并提出效率和排放兼顾的正丁醚低温燃烧发动机清洁高效的运行策略；最终为发展正丁醚的燃烧化学机理提供可靠依据，为正丁醚发动机的燃烧优化和排放控制提供理论和技术支撑。

Di-n-butyl ether, which could be produced from lignocellulosic biomass, is a promising novel alternative oxygenated biofuel. Based on experimental and simulation methodologies, this proposal aims to conduct fundamental study on the auto-ignition processes of di-n-butyl ether (DBE) at engine-like conditions, and on the combustion and emissions characteristics of novel engine combustion strategies fuelled with DBE. Through a systematic study, the high pressure auto-ignition characteristics and mechanisms of DBE at homogeneous and chemical-transport coupling conditions are to be illustrated, the physical and chemical ignition delay times in the DBE spray ignition processes at high pressure conditions will be decoupled, and the effects of the diluent and active components in exhaust gas recirculation on DBE spray ignition will be revealed. Further, the ignition, heat release and emissions characteristics of DBE engine under premixed low-temperature combustion modes are to be studied, with an operational strategy simultaneously considering engine efficiency and emissions to be proposed. Finally, this study will provide reliable evidences for DBE combustion chemical mechanism development, and provide theoretical and technical support for the combustion optimization and emissions control in DBE engines.