Also known as air doors, air curtains are fan-powered machines that blow controlled air streams across doorways or other openings to develop an invisible air barrier. This allows them to separate two environments without limiting their access or visibility to people or cars.
They also help improve the indoor air quality of a building by controlling conditioned or heated air, controlling humidity, plus preventing pest and contaminant entry. There are different types of air curtains depending on your budget, purpose, and the location, size, and height of your doorway.
While most air curtains are installed horizontally over the door, you can have yours installed vertically on the sides of the door.
When turned on, air curtains suck in the air via the intake grille into the fan housing. Most intake grills come with filters to protect the fans, heat exchanger, and other electronic parts from dust and debris.
The fan then accelerates the air, which goes into a plenum. The plenum allows the air curtain to evenly distribute the air along the discharge nozzle’s full length, resulting in laminar airflow.
The curtains have airfoil-shaped vanes inside the nozzle to create uniform air streams with minimal turbulence. You can adjust the vanes to alter the air discharge angle for optimum performance.
The air from the nozzle forms a jet stream to the floor, and around 80% of the air goes back into the curtain, while approximately 20% is released into the environment.
If you have a very big discharge angle, the curtain will not stop enough wind from getting in near the floor, while a very small discharge angle means little horizontal force preventing significant wind from entering.