blowdowns

Noun

blowdown (countable and uncountable, plural blowdowns)

1. (chemical engineering) The removal of liquid and solid hydrocarbons from a refinery vessel by the use of pressure.
2. (industrial engineering) Cooling fluid discharged from a plant at the end of its cycle.
3. Uprooting, overtopping, or bole breakage of trees by the wind; windthrow and windsnap.
4. The action of aerodynamic forces to tend to cause a deflected control surface to return to its neutral position, or prevent the surface from deflecting past a certain point.
   • At higher airspeeds, the 737's maximum rudder deflection is limited by blowdown, helping to prevent flight-control inputs from overstressing the aircraft's vertical stabilizer.
5. (informal) An instance of blowing down with compressed air.
   • Give these parts a blowdown with your air hose before you put them in the ultrasonic cleaning tank.