煤直接液化柴油DCLD最近在我国率先成熟、大批量生产。针对其迥异于石化柴油的烃族组成、理化和燃烧特性，本项目系统研究其替代物燃烧反应机理。据可行性、简易性、相似性、实用性，选择环烷烃及其与其它烃类（如链烷烃）的混合物作替代物。提出单组分燃料详细机理构建策略，燃烧机理由核心机理和阶梯式扩展机理构成。揭示反应速率受温度的影响机制。考虑燃料间重复反应、剩余反应、纯燃料燃烧典型特征再现等，提出并实施多组分燃料详细机理构建策略。针对传统计算奇异摄动CSP方法仅能局部分析的缺陷，提出积分CSP高保真度机理简化原理和算法。用激波管等试验验证详细机理。用多步直接关系图法得框架机理，用积分CSP得全局简化机理。构建发动机燃烧模拟计算平台，添加燃料特性预测模型，改进燃料蒸发模型，添加湍流与化学反应相互作用模型，用简化机理3D数值模拟DCLD发动机缸内过程。在电控柴油机上研究DCLD着火、燃烧与排放，及喷油器结构参数、喷射控制参数、运转工况的影响规律。在缸内强烈瞬变复杂环境下，检验全局简化机理的有效性。本研究为柴油机可控清洁高效低温燃烧技术的发展提供依据。

Direct coal liquefaction diesel (DCLD) has been put into mass production firstly and recently as a new alternative fuel for diesel in China. Because of its different hydrocarbon groups composition, combustion, physical and chemical properties from petro-diesel, the project systematically studies the combustion mechanism of its surrogates。Considering feasibility, simplicity, similarity and practicability, bicyclo-alkane and its mixture with other alkanes are specially-chosen as the surrogates. Based on reaction sorting, a detailed kinetic mechanism construction principle for single-constituent surrogate is proposed. The combustion mechanism consists of core mechanism and step-expanded mechanism. The effect of temperature on reaction rate is uncovered. In view of inter-fuel repeatable reactions and surplus reactions as well as typical characteristics representation for pure constituent, a methodology for constructing detailed kinetic mechanism for multi-constituent surrogates is also given. To overcome the analytical locality of conventional CSP（computational singular perturbation）, an integral CSP algorithm is put forward for reducing comprehensive mechanism with hi-fidelity. Shock tube experiments and others are performed to verify the comprehensive mechanisms. Skeletal mechanisms are derived with Directed Relation Graph and global mechanisms using integral CSP. 3D combustion simulation model is created for engine operation with fuel property prediction model, fuel evaporation model and turbulence-reaction interaction model.The global mechanisms are then employed to simulate in-cylinder combustion. Finally, on an electrical controlled diesel engine, the ignition, combustion and emissions of DCLD are investigated with global mechanisms validated in an intensely unstable complex combustion environment. The effects of injector structure, injection parameter and operation condition on ignition and combustion are researched. The study provides a theoretical support for controllable clean and high-efficiency LT combustion.