凹半球形轨道分子屏分子流场理论计算

借助一个封闭的球形理论模型，对稳态非均匀分子流环境下的凹半球形轨道分子屏进行研究，计算了试验区分子数密度分布情况，讨论了主要影响因素，结果显示，利用凹半球形轨道分子屏可获得１０＾８分子数／ｍ＾３（等效于１０＾－１２Ｐａ）的极高真空，分子屏出气对试验区分子数密度的贡献是主要的，分子屏粘附系数增大不能有效改善空载情况分子屏试验区的真空度。

Theoretical Calculation of Molecular Flow Fieldfor the Concave Hem ispherical W ake Shield Facility

In this paper, the concave hem isphericalw ake shield facility ( C H W S F) isstudied w hich is in the state of steady, non uniform w ith the closed sphericaltheoreticalm odel. The distribution ofthe m olecularnum berdensity ofthe experim entalzone is calcu lated and the m ain effect factors are discussed. The result show s thatthe C H W S Fcan ob tain extrem e high vacuum levelw hose m olecular num ber density is about 108m - 3,the m aincontribution to the m olecular num ber density com es from the outgas ofthe C H W S F, andthe increasem ent of the coherent coefficient of the C H W S F can't effectively im prove thevacuum levelon occasion of absence ofgasload.