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moves to the trailing edge point, the vortex shedding stops, the airflow
around the trailing edge point leaves smoothly, the boundary layer of
the upper and lower wings forms a stable state, the velocity difference in the outflow area of the boundary layer reaches the maximum,
the attached vorticity around the airfoil reaches the maximum, the
lift reaches the maximum, and the airfoil flow around the airfoil
completes the starting process (as shown in Fig. 2.37).
It should be noted that if the airfoil accelerates or decelerates again,
the stable boundary layer changes from one stable boundary layer to
another. The vortex shedding at the trailing edge will continue until
a new stable boundary layer is formed (as shown in Fig. 2.38). After
Fig. 2.37 Stable stage of boundary layer (uniform speed)
Fig. 2.38 Periodic shedding stage (deceleration) of rear edge separation vortex