内燃机跨临界/超临界燃料喷雾混合过程的机理与模型  

Mechanism and Modeling of Transcritical/Supercritical Fuel Spray and Mixture Formation in Internal Combustion Engines

作　　者：解茂昭[1] 

机构地区：[1]大连理工大学能源与动力学院,大连116024

出　　处：《燃烧科学与技术》2014年第1期1-9,共9页Journal of Combustion Science and Technology

基　　金：国家自然科学基金资助项目(51376029)

摘　　要：高密度低温燃烧等内燃机燃烧新概念的提出,使得跨临界/超临界燃料喷射与喷雾混合成为内燃机研究者面临的一个重要课题.跨临界/超临界下的液体射流与喷雾形成具有与亚临界工况本质不同且极其复杂的机理.首先对跨临界/超临界液体射流喷雾的特征与机理做了简要介绍;然后,对迄今国内外在该领域的研究进展进行了比较系统全面的评述,同时指出了其局限与不足.在全面审视前人关于直喷式内燃机燃料喷雾混合过程的机理与模型研究的基础上,提出一个新的跨临界/超临界环境下液体燃料喷射与混合气形成的数理模型——"混合层回缩"(MLR)模型;并进而建议,采用微观、介观与宏观研究相结合的5步策略,构建直喷式发动机亚临界/跨临界/超临界燃料喷雾混合过程的全工况统一模型.With the development of new combustion concepts represented by high density and low temperature com-bustion,transcritical/supercritical fuel spray and mixture formation become an important subject for internal combus-tion engine researchers. The mechanism of liquid injection and spray formation in transcritical/supercritical state is extremely complex and essentially different from subcritical sprays. In this paper,firstly,the characteristics and mechanism of transcritical/supercritical jet and spray are introduced briefly. Then,a comprehensive review of the progress so far made in this field is presented,and the existing limitations and problems in the research are pointed out. Based on the previous studies on the mechanism and modeling of fuel spray and mixing process in direct injection engines , a new model for the liquid fuel injection and mixture formation in the transcritical/ supercritical environment,called ＆quot;mixing layer regress＆quot;（MLR）model,is proposed;finally,a five-step multiscale strategy is suggested for the development of a unified and comprehensive model of sub-/trans-/supercritical fuel spray mixing process,which is applicable to all working conditions of direct injection engines.

关 键 词：内燃机 跨临界 超临界 燃料喷雾 混合层回缩模型 多尺度 

分 类 号：TK401[动力工程及工程热物理—动力机械及工程]