郭晓平;王占杰
大连理工大学
摘要：不改变燃烧室体积,通过改变燃烧室的口径比和径深比,对柴油机工作过程进行了模拟计算。燃烧模型取4步简化动力学模型,湍流模型取修正k-ε模型。计算区域除气缸和燃烧室外,还包括进、排气支管。计算结果表明,随着口径比的减小,缸内挤流强度增加。对于空间雾化燃烧的直喷式柴油机,将燃烧室结构设计成油注形状,可以利用燃烧波在燃烧室内产生较大尺度的垂直涡流,有利于增强燃油喷射效应,从而提高油气与空气的均匀混合质量,提高柴油机的经济性,同时也有利于降低NO排放。
关键词： 柴油机;;数值计算;;流场;;口径比;;径深比
Abstract: The working process of diesel
engine is simulated by changing flow field,surface-volume ratio,diameter-depth
ratio of combustion chamber with the same volume.A 4-step simplified dynamic
model is for combustion model and modified k-(model for turbulent model.Besides
cylinder and combustion chamber,intake and exhaust manifold is calculated.The
calculation results shows that squashing inside cylinder gets much stronger
when surface-volume ratio becomes smaller.For the direct injection diesel
engine by atomizing combustion,the combustion chamber is shaped into oil column
to create vertical swirl in combustion chamber by combustion wave so that to
improve fuel injection effect and get homogeneous air/fuel mixture and high
economy and low NO emission.
Keywords: Diesel Engine;Numerical
Calculation;Flow Field;Surface-volume Ratio;Diameter-depth Ratio
基金项目: 本项目在AMD平台上完成并受到AMD大学计划支持
参考文献：
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Kim.FlowAnalysis of the HelicalIntakePortCylinder of a Direct
InjectionDiesel Engine.SAE Paper 952069
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[4]解茂昭,内燃机计算燃烧学.大连:大连理工大学出版社,1995.
[5]郭晓平,王占杰,许锋.直喷式柴油机两段喷射计算模拟,热科学与技术,2004.12(4):343~347
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