Concrete blinds Soviet hospital Bashny.Net

These are concrete visors are in a hospital in Moscow.









It appears this lamellar roofs, which are set to improve ventilation in the room.

The principle of operation is as follows:
The warm air in any room upstairs the ceiling and wants to be even higher, and travel along the cold bottom.

When the window is open - the warm air starts to come out on top of the window to the street, creating a craving that draws cooler air from the street. It is with a simple box.

When the "output" of warm air from the window to put the "wing", such as in an airplane, the warm air at the exit of the room falls below a profile of the wing, creating a lifting force like an airplane wing, and even quicker to get out of the edge rush up , accelerating.

Thus creating an even stronger pull cold air at the bottom, which will be quickly sucked into the room.
Zero cost for the acceleration of the fan ventilation, the forces of nature just amplified cunning.