碳化硅超高温合成炉内气体流动特性研究  

Numerical Simulation of Gases Flow Field in Ultra-High-Temperature SiC Synthesis Furnace

作　　者：陈杰[1] 李阳[1] 

机构地区：[1]西安科技大学材料科学与工程学院,西安710054

出　　处：《真空科学与技术学报》2016年第3期367-371,共5页Chinese Journal of Vacuum Science and Technology

基　　金：国家自然科学基金项目(51074123);陕西省教育厅科研计划项目(12JKI0785);榆林市产学研合作项目(2011)西安科技大学博士基金(2011QDJ022)资助

摘　　要：通过对碳热还原法合成SiC冶炼炉的复杂炉况进行数值模拟及实验,研究了单热源炉内气体流动的动态变化规律。研究表明,单热源炉内气体的流动呈现三维立体多向流规律,气体流动依次沿着:热源延伸方向、垂直热源延伸方向、环绕SiC结晶筒方向流动。根据气体流动特性,可以在环绕结晶筒气流出现的以外部分加入少量木屑,以增加气孔率,使得气体顺利向外部扩散,有利于炉内压力的释放;控制炉体长度,可以在一定程度上减少平行热源延伸方向气体流动的范围,从而缩小成品的气孔大小,提高SiC成品质量。The 3-D gases flow-field,in ultra-high-temperature furnace for SiC synthesis by carbothermal reduction,was empirically approximated,mathematically modeled,theoretically analyzed in fluid mechanics and thermodynamics,and numerically simulated with software Gambi. The impact of the synthesis conditions,including but not limited to the fields of temperature,gas-flow fields and pressure,reaction time and heating rate,on the microstructures and properties of bulk SiC was investigated. The simulated results show that depending on the temperature of heater and reaction time,the co-existence of laminar flow in three orientations： around the SiC-growth bucket,perpendicular to and parallel to the heatsource axis,negatively affects the SiC quality. Interesting finding was that addition of a little sawdust outside the front of the annular flow around the SiC-growth bucket,and reduction of furnace length insignificantly improve SiC quality; and the possible mechanisms responsible for the SiC quality improvement were tentatively discussed.

关 键 词：超高温合成炉 碳化硅 流动特性 数值模拟 

分 类 号：TQ173[化学工程—搪瓷工业]