Air Curtain

An air curtain is a method of containing oil spills. Air bubbling through a perforated pipe causes an upward water flow that slows the spread of oil. It can also be used to stop fish from entering polluted water. Also called a pneumatic barrier.An air curtain is a fan-powered device used for separating two spaces from each other.
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the flow of forced air that maintains temperature differences between refrigerated displays and the store, or between the inside and outside of the store. Air curtains are designed to minimise the psychological barriers posed by tangible doors separating

A method of containing oil spills. Air bubbling through a perforated pipe causes an upward water flow that slows the spread of oil. It can also be used to stop fish from entering polluted water.