average free distance

• 平均自由程

average free distance的用法和样例：

例句

1. For perfectly lattice-matched superlattices, a minimum thermal conductivity is observed when the period length is of the order of the effective phonon mean free path.
   模拟结果表明，在晶格匹配的超晶格中，当周期长度同声子平均自由程相当时，超晶格导热系数将出现最小值。