空间不变性 meaning in English

space-invariance
spatial invariance

In order to derive this equation , one has to assume no spatial variability in k , f and n , to neglect the effect of capillary rise above the groundwater table , and to invoke the dupuit - forcheimer approximation , which states that the hydraulic head is independent of depth
图1潜水面的示意图为了利用dupuit - forcheimer假设推导出以上的方程,必须假设k , f以及n t在整个潜水面上的空间不变性,同时忽略潜水面上的水分的毛细运动