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When my window is fully open, I can feel the breeze from outside. But when I put on my mosquito net, the breeze gets blocked almost completely. Why does mosquito net block the breeze, even though its mostly porous?

Edit: The net is made up of metal wires about half a millimeter thick, probably made of aluminium. The net has a pore size less than a mosquito length, about 3 mm.

enter image description here

Picture credit: amazon

AlphaLife
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1 Answers1

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Imagine each wire as a cylinder that is applying drag on the incoming air. This drag creates a turbulent wake surrounding the wire. The eddies created in this turbulence are eating up the breeze's energy via frictional dissipation.

A schematic of the view from inside the room:

enter image description here

philipxy
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String bean 99
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