摘要
从段法基本概念出发,推得了柴油机缸内火焰段对整个缸壁段的辐射全交换面积计算式,并以此为基础给出了缸内辐射传热的单区段法模型。与实验结果比较表明,该模型能更准确地模拟缸内辐射传热量。将该模型与传统的单区模型比较,可得到壁面有效吸收系数的表达式,它是壁面黑度和火焰辐射系数的函数,并随壁面黑度的增大而增大,随火焰辐射系数的增大而减小。而传统的方法认为壁面有效吸收系数仅为壁面的黑度的函数。
Based on the conception of zonal method, the total radiant exchange area for flame zone to surface zone of the diesel in-cylinder was derived. A single zonal method was developed accordingly to predict the diesel in-cylinder radiation heat transfer. Comparison between the calculated results of the heat flux across the in-cylinder surface with those measured and those reported results indicate that the current method is more accurate. Compared with the traditional single model, the surface effective absorption coefficient was obtained, which is the function of the surface emissivity and the flame radiation coefficient, while in the traditional model, it is only the function of the surface emissivity. The surface effective absorption coefficient increases with the increase of the surface emissivity but decreases with the increase of the flame radiation coefficient.
出处
《热科学与技术》
CAS
CSCD
2005年第3期237-240,共4页
Journal of Thermal Science and Technology
基金
江苏省教育厅高校自然科学指导性计划基金(03KJD140022).
关键词
柴油机
辐射传热
辐射全交换面积
diesel engine
radiation heat transfer
total radiant exchange area
