- The suction surface (a.k.a. upper surface) is generally associated with higher velocity and lower static pressure.吸力面，即上表面，一般是高速和低静压
a.k.a: also known as
- The pressure surface (a.k.a. lower surface) has a comparatively higher static pressure than the suction surface. The pressure gradient between these two surfaces contributes to the lift force generated for a given airfoil.
压力面，即下表面，静压相对较高，
两表面之间的压力梯度产生升力。