真空 ›› 2024, Vol. 61 ›› Issue (3): 13-19.doi: 10.13385/j.cnki.vacuum.2024.03.03
韩峰, 张志军, 张世伟, 王晓伟
HAN Feng, ZHANG Zhi-jun, ZHANG Shi-wei, WANG Xiao-wei
摘要: Knudsen泵作为一种微型泵,在微机电系统(MEMS)中具有广泛应用。本文提出了一种具有不同表面反射系数的棘齿型Knudsen泵,通过直接模拟蒙特卡罗(DSMC)方法对该泵内He-Xe混合气体流动特性进行了数值模拟研究。结果表明:表面反射特性对Knudsen泵内的流场特性和气体分离特性影响巨大,不同的表面反射特性导致了Knudsen泵内不同的热驱流动机理;三角形倾斜边的αn=σt=0时Knudsen泵内主要热驱流动为辐射流,有利于气体分离,而αn=σt=1时Knudsen泵内主要热驱流动为热边缘流,对气体分离没有明显有利作用;三角形倾斜边的αn=σt=0时He和Xe的速度和扩散速度在三角形棘齿上顶点附近差异最大,而αn=σt=1时在三角形棘齿左侧顶点附近差异最大;越轻的气体流动速度和扩散速度越快。本文可为实际工程应用中微型气体分离装置的设计和生产提供理论依据。
中图分类号: TB71+1;O356
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