中文摘要：

利用直接模拟蒙特卡洛方法（DSMC），模拟了气体凝聚团簇源的引出口尺寸和中心位置不同的条件下，Cu团簇的尺寸分布以及模拟了随着时间的增长，腔内团簇数目的变化．模拟结果表明：引出口的直径越大，产生大团簇的比例越小；在引出口的直径相同的情况下，引出口的中心位置偏离坐标原点比在原点产生的大团簇的比例要大；随着时间的增长，腔内团簇数目先变多后变少．

英文摘要：

In a gas aggregation cluster source, the size distributions of the Cu clusters in various sizes and central positions of the exit nozzle and the change of the number of clusters in the chamber with the increase in time are studied by direct simulation Monte Carlo method. The results show that that size of cluster increases with the decrease in the diameter of the exit nozzle; larger clusters can be obtain in this situation that the central positions deviate the origin of the coordinates; the number of clusters in the chamber increases with the increase in time in the initial stage; soon after that, the number of clusters in the chamber decreases with the increase in time.