过渡面 meaning in English

fillet surface
transition surface
transitional surface

Calculation of confirmation to transitional surface range in the airfield clearance rules
机场净空规定过渡面范围的计算确定
The quality of the model affects the fem mesh generation . the main issue is the disposal of important small features such as the blend between two faces
这方面主要的技术难题涉及一些重要特征的处理，比如面和面之间的倒角或面与面之间过渡面的处理等。