principal section meaning in English

重面
主断面
主截面
主剖面

This rotation can be simplified by plotting the positions of the principal sections and principal axis on a stereographic net as described by jessop and wells from the rotations recorded .
按照杰索普和威尔士所论述的方法，根据记录下来的转动角，把主截面和主轴的位置画到一个极射赤平投影网上，可使上述过程简化。
Door design based on hard data points and principal section
基于设计硬点和主断面的车门设计