采用有限元计算方法,研究了CVI反应器内部的流场特征.对于形状简单的构件,构件的放置方式和阵列对气体的流动状态具有显著的影响.与横向阵列相比,纵向阵列能充分保证构件沿其长度方向流场均匀性,减小回流现象;在反应器中,随着纵向阵列试样数量的增加和分布均匀性的提高,气体流动速度增大,流场均匀性提高.减少反应器内部的自由空间,是提高流场品质和化学气相沉积效果的关键.基于减少反应器内部的自由空间的原则,针对杯形复杂构件,提出了通过加入与其几何形状相适应的导流板工装,有效避免了在构件内部和外部形成回流区,实现流场的优化设计.
参考文献
[1] | EVANS A G .Perspective on the development of high toughness ceramics[J].Journal of the American Ceramic Society,1990,73(02):187-206. |
[2] | NASLAIN R .Processing of ceramic matrix composites[J].Key Engineering Materials,1998,164-165:3-8. |
[3] | 徐永东,成来飞,张立同,尹洪峰.连续纤维增韧碳化硅陶瓷基复合材料研究[J].硅酸盐学报,2002(02):184-188. |
[4] | 肖鹏,徐永东,黄伯云.CVI法快速制备C/SiC复合材料[J].硅酸盐学报,2002(02):240-243. |
[5] | STINTON D P;CAPUTO A J .Synthesis of fiber-reinforced SiC composites by chemical vapor infiltration[J].American Ceramic Society Bulletin,1986,65(02):347-350. |
[6] | CAPUTO A J;LACKEY W J .Fabrication of fiber reinforced ceramic composites by chemical vapor infiltration[J].Ceramic Engineering and Science Proceedings,1985,5(7-8):654-667. |
[7] | XU Yong-dong;ZHANG Li-tong .Three dimensional C/SiC composites prepared by chemical vapor infiltration[J].Journal of the American Ceramic Society,1997,80(07):1897-1900. |
[8] | Xu YD.;Cheng LF.;Yan DT.;Zhang LT. .Microstructure and mechanical properties of three-dimensional carbon/silicon carbide composites fabricated by chemical vapor infiltration[J].Carbon: An International Journal Sponsored by the American Carbon Society,1998(7/8):1051-1056. |
[9] | 肖鹏,徐永东,张立同,成来飞.CVI反应器气体流动可视化发烟系统[J].航空材料学报,2000(02):46-48,54. |
[10] | 姜开宇,李贺军,侯向辉,李克智.轴对称C/C复合材料件等温CVI过程的数值模拟研究[J].西北工业大学学报,2000(04):665-668. |
[11] | MCALLISTER P;WOLF E E .Simulation of a multiple substrate reactor for chemincal vapor infiltration of pyrolytic carbon with carbon-carbon composites[J].AICHE Journal,1993,39(07):1196-1209. |
[12] | TAI N H;CHOU T W .Analytical modeling of chemical vapor infiltration in fabrication of ceramic composites[J].Journal of the American Ceramic Society,1989,72(03):414-420. |
[13] | Starr TL. .GAS TRANSPORT MODEL FOR CHEMICAL VAPOR INFILTRATION[J].Journal of Materials Research,1995(9):2360-2366. |
[14] | LI Kezhi,LI Hejun,JIANG Kaiyu,HOU Xianghui.Numerical simulation of isothermal chemical vapor infiltration process in fabrication of carbon-carbon composites by finite element method[J].中国科学E辑(英文版),2000(01):77-85. |
[15] | 吴望一.流体力学[M].北京:北京大学出版社,1998:91. |
[16] | 鲁德洋.冶金传输基础[M].西安:西北工业大学出版社,1991 |
上一张
下一张
上一张
下一张
计量
- 下载量()
- 访问量()
文章评分
- 您的评分:
-
10%
-
20%
-
30%
-
40%
-
50%