基于漫反射原理的撞壁油膜特性方法研究  

Investigation of Impingement Oil Film Based on the Diffuse Reflection Principle

作　　者：董伟[1] 李志辉[1] 宋佰达 杜耀东[1] 周玮[1] 阮尔博 Dong Wei;Li Zhihui;Song Baida;Du Yaodong;Zhou Wei;Ruan Erbo(State Key Laboratory of Automobile Simulation and Control,Jilin University,Changchun 130022,China)

机构地区：[1]吉林大学汽车仿真与控制国家重点实验室,吉林长春130022

出　　处：《内燃机学报》2020年第6期497-504,共8页Transactions of Csice

基　　金：国家自然科学基金资助项目(51176136).

摘　　要：为了研究汽油缸内直喷(GDI)发动机喷雾撞壁油膜特性,基于漫反射原理设计并搭建了定容测试系统.基于Python的Opencv软件以及Matlab软件设计开发了图像处理程序,进行了油膜厚度测量的标定试验,实现了对油膜面积、油膜最大厚度、油膜平均厚度和燃油附壁率等特性参数的提取.应用该测量方法研究了不同撞壁距离对油膜特性的影响,结果表明:随着撞壁距离的增加,油膜厚度及燃油附壁率逐渐减小,油膜面积变化不大.其他条件不变,撞壁距离分别为30、40、50和60 mm时对应油膜最大厚度的最大值分别为37.2、30.9、25.8和19.0μm;油膜平均厚度的最大值分别为23.7、16.4、11.2和7.8μm;最大油膜质量分别为4.85、4.00、3.29和2.55 mg,对应的燃油附壁率分别为32.3%、26.7%、21.9%和17.0%.该测量方法对进一步研究和掌握GDI发动机撞壁油膜特性具有实际意义.In order to study the characteristics of the spray impingement oil film in gasoline direct injection(GDI)engines,a constant volume testing system was designed and built based on the principle of diffuse reflection.The image processing and analysis program were developed by using Python-based Opencv and Matlab,and then the calibration experiment of oil film thickness measurement was conducted.The extraction of oil film characteristic parameters such as area,maximum thickness,average thickness and adhesion rate of oil films were realized.This method was applied to study the effect of wall impact distance on oil film characteristics.These results show that with the increase of wall impact distance,the thickness and the adhesion rate of oil film decrease gradually,and the area of oil film does not change much.When the wall impact distances are 30,40,50 and 60 mm,the maximum thickness of the corresponding oil films are 37.2,30.9,25.8 and 19.0μm respectively;the maximum thickness of the average oil films are 23.7,16.4,11.2 and 7.8μm respectively;the maximum of oil film masses are 4.85,4.00,3.29 and 2.55 mg respectively;and the corresponding fuel adhesion rate are 32.3%,26.7%,21.9%,and 17.0%respectively.This measurement method was verified to be a useful tool to investigation the impingement oil film on the cylinder wall of GDI engines.

关 键 词：汽油机 漫反射原理 油膜厚度 撞壁油膜 

分 类 号：TK411[动力工程及工程热物理—动力机械及工程]