燃烧室部件传热空间非均匀性对缸内燃烧的影响

EFFECT OF HEAT TRANSFER SPACE NON-UNIFORMITY OF COMBUSTION CHAMBER COMPONENTS ON IN-CYLINDER COMBUSTION IN DIESEL ENGINE

将所有燃烧室部件(气缸盖-气缸套-活塞组-润滑油膜)作为一个耦合体,在对耦合体进行三维传热数值模拟的基础上,利用分区求解、边界耦合法建立缸内工作过程与燃烧室部件的三维耦合计算模型,从而实现缸内工作过程与燃烧室部件的耦合三维仿真模拟,以此考察燃烧室部件传热空间非均匀性对缸内燃烧的影响。研究结果表明,燃烧室部件传热空间非均匀性在喷雾过程几乎对燃烧没有任何影响,可以忽略不计;燃烧过程后期,这种传热空间非均匀性才越来越明显,由此可以推断,燃烧室部件传热空间非均匀性的影响在排气过程将进一步加剧。

Combustion chamber components （cylinder head-cylinder liner-piston assembly-oil film） were treated as a coupled body. Based on the three-dimensional numerical simulation of heat transfer of the coupled body, a coupled three-dimensional calculation model for the in-cylinder working process and the combustion chamber components was built with domain decomposition and boundary coupling method, which adopts the coupled three-dimensional simulation of in-cylinder working process and the combustion chamber components. The simulation was applied in the influence investigation of the space non-uniformity in heat transfer among combustion chamber components on in-cylinder combustion. The results show that the space non-uniformity in heat transfer among the combustion chamber components has nearly no effect on combustion at the stage of spray. The effect of heat transfer space non-uniforlnity of combustion chamber components enhances at the later stage of combustion. Moreover it can be deduced that the effect of heat transfer space non-uniformity would enhanced further during exhaust stroke.