入口条件对D4合成石英玻璃的影响  

Effects of Entrance Conditions on Fused Silica Glass Synthesis Using D4

作　　者：黄泽宇 黄耀松[1] 陈靖 郑丽丽[1] Huang Zeyu;Huang Yaosong;Chen Jing;Zheng Lili(School of Aerospace Engineering,Tsinghua University,Beijing 100084,China)

机构地区：[1]清华大学航天航空学院,北京100084

出　　处：《燃烧科学与技术》2018年第6期477-486,共10页Journal of Combustion Science and Technology

基　　金：国家重点研发计划资助项目(2016YFB0303801)

摘　　要：通过对D4合成石英玻璃过程的数值模拟研究,分析了氢氧当量比、氢氧质量流量、D4和载气总流量对沉积面温度和组分分布以及沉积位置的影响,并根据石英玻璃软化温度优化了沉积面形状.研究结果表明,氢氧当量比为1.0时,沉积面上温度和组分浓度梯度都比较大.适当地降低当量比或者氢氧质量流量,增加中心入口流量,可以减少OH生成,提高SiO_2产量,改善沉积面上组分浓度分布均匀性;但流量过低,会导致沉积效率下降.沉积位置应根据火焰温度进行调整,沉积面上非均匀的温度分布一定程度上是由于物理模型中沉积面形状的不合理造成的,偏平状的沉积面更加符合实际情况.This paper presents numerical studies of silica glass synthesis conducted via chemical vapor deposition(CVD)using D4 instead of traditional SiCl4 as the source gas. Herein,effects of the H2/O2 equivalence ratio,and the mass flow rate of H2/O2 and the D4/carrier gas flow rates on the temperature and species concentration distributions on the deposition surface are investigated,together with their impacts on substrate placement and the shape of the deposition surface. The temperature gradient is large when the equivalence ratio is 1.0. Reducing the equivalence ratio or mass flow rate of H2/O2 and increasing the flow rate of D4/carrier gas are beneficial to the homogeneity of glass,such as low OH and high SiO2 production. However,reducing the flow rate will lower the deposition efficiency. The location and the shape of the deposition surface changes with the flame temperature and its distribution. Inhomogeneity in the temperature distribution also affects the shape of the deposition surface to a certain extent,wherein a flat shape is preferable.

关 键 词：石英玻璃 D4反应机理 反应流 数值模拟 

分 类 号：TK16[动力工程及工程热物理—热能工程]