摘要
为了得到圆管状内壁面通过管口辐射传递的方向分布特性 ,给出了圆管状内壁面单元间辐射传递系数RD的蒙特卡罗求解方法 ,研究了当内壁为等温灰体、漫发射、漫反射时 ,管内壁发射率、管长与半径比的变化对管口表面当量定向发射率的影响 ,结果表明 :总趋势为管长与半径比增加 ,管口表面当量定向发射率极值点向小角度的天顶角方向移动 ,在管长与半径比较大时 ,随管长增加、管内壁发射率ε减小 。
To obtain the direction distribution of radiation transmission through the tube end of a cylindrical inner-wall surface, the authors have introduced a Monte Carlo method for solving the radiation transmission factor RD among cylindrical tube inner-wall surface elements. With the inner wall being an isothermal gray body of a diffuse emission and diffuse reflection, the impact was studied of the change of tube inner-wall emission rate, and of the ratio of tube length to radius on the equivalent directional emission rate of a tube-end surface. The study results indicate the following general tendency. With the increase in tube length-to-radius ratio, the maximum value point of the equivalent directional emission rate of the tube-end surface will shift in the direction of a small-angled zenith angle. When the ratio of tube length to radius is relatively great, the tube inner-wall emission rate will decrease with an increase in tube length. With a relatively small tube outlet surface the equivalent orientation emission rate in the zenith angle direction will increase.
出处
《热能动力工程》
EI
CAS
CSCD
北大核心
2004年第1期48-51,共4页
Journal of Engineering for Thermal Energy and Power
基金
哈尔滨工业大学校内博士启动基金资助项目 (0 15 0 2 3 49)
关键词
辐射传热
蒙特卡罗法
圆管
当量定向发射率
radiation heat transfer,Monte Carlo method, tube, equivalent orientation emission
