aerodynamic brake
/ɐdʒˈʌstmənt fɔː ˈvɜːtɪkəlsˈɜːkəl ˈɪmɪdʒ/
n
中文：气动刹车
Meaning：Emergency braking system; it consists of shutters attached to the blades, which automatically deploy when the wind turbine gathers too much speed.
中文：气动刹车