In the past, the exhaust pipes of low-rise houses were mostly made of bricks. With the emergence of high-rise and super-high-rise buildings, as well as the requirements of reducing weight, volume and simple installation, the exhaust duct prefabricated by sulphoaluminate cement and alkali-resistant glass fiber mesh or ordinary silicate cement and steel wire mesh was born. ?
Exhaust principle:
When the flue gas from the air inlet is discharged into the flue, it will meet the flue gas discharged upward from the lower floor. When the two air streams meet, a vortex and an air curtain will be formed, which will hinder the upward movement of the lower flue gas. Once the fire check valve is stuck by oil pollution and can't be opened, the smoke will flee indoors because of its upward movement.
In order to overcome the technical problem of smoke smell, the solution is to use the principle of dynamic and static pressure conversion of aerodynamics to set a patented variable pressure component for extracting air and accelerating air flow in the flue, which was developed by Jiangsu Zitai Institute of Architecture and Technology, so that the smoke can be converted from dynamic and static pressure at a specific position, and the exhaust port of a kitchen or bathroom without a range hood is in a negative pressure state.
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