透水边界的英文：
permeable boundary

permeable是什么意思：
a. 有浸透性的,能透过的

This membrane is semi-permeable.
这层膜是半渗透性的。

The waste material is placed in cells with permeable membranes
废液置于有渗透膜的槽中。

The major difference is that geological structures have limited permeability.
主要的问题是地质结构的渗透性有限。

The permeability of a soil is important for calculations of underground flow
土的渗透性对于地下液流的计算很为重要。

Histamine causes vasoconstriction and increased permeability of small venules.
组织胺能引起血管收缩，并增强小静脉的透性。

boundary是什么意思：
n. 边界；范围；分界线

Boundary is used with administrative areas smaller than a state or country boundary
用于指行政区域,范围比国家小

An exact artificial boundary condition is obtained on a spherical boundary by a constructive method.
同样，采用构造法在球面上获得了精确的无反射人工边界条件。

There are no indecisive boundaries between the two opinions.
这两种意见界线分明。

The boundaries are clearly marked off on the map.
界线清清楚楚地在地图上标了出来。

Boundaries of the polygon may extend to infinity.
多角形的边界可以延伸到无穷远处。