优化CVI反应器气体流场的可视化研究

CVI(化学气相浸渗 )反应器内气体的输运对基体的沉积速度与沉积质量有重要的影响。用一套结构简单、可操作性强的气体流动可视化设备 ,对底部进气的等温等压CVI反应器内气体流场进行了模拟研究 ,得到如下结论 :在气体入口处采用涡流器与多孔整流器 ,能消除中心射流并减小上部回流区域 ,扩大反应器的有效使用空间 ;使衬底与气体主流方向成一定的夹角 ,能有效阻止气体边界层的分离

Visual research on optimization of flow in CVI reactors

The effect of fluid flow in the CVI reactors on the deposition velocity and quality is of great importance. On the base of the flow visualization equipment developed preserving simplicity of construction and operation, the simulation studies on flow in an isothermal, isobaric CVI reactor with let in gas from bottom was conducted. The following results were obtained. (1) An elimination of the center jet, a minimization of the top return flow and an enlargement of usable room on a reactor are achieved by using a whirlpool and a rectifier, and (2) an angle between substrate and flow is good for adherence of boundary layer on the substrate.