网址：www.fengguanjiagong.com 2021-04-28 作者：admin 阅读：
Flue is an important part of residential ventilation system. The code for design of residential buildings issued by the Ministry of construction in 1999 regulates the design of flue. However, many buildings still have the problem of smoke-free road design, and the residential areas are seriously polluted by smoke, odor and cross pollution.
1、 Causes of poor smoke exhaust in flue
According to the general rules for design of civil buildings, the height of the flue extending out of the roof shall not be less than 0.6m. However, the implementation of this provision is different in some places. Some houses with flue are designed with single type of flue, which is easy to cause oil fume backflow and odor. In addition, in order to increase the kitchen area, some buildings have reduced the cross-sectional area of the vertical flue, and there is no mechanical smoke exhaust device, so that the flow of the smoke exhaust system is very small, resulting in poor smoke exhaust.
2、 Understand the classification of residential flue
The current residential flue is generally divided into: single flue type, primary and secondary type, variable pressure type, check valve type.
Single flue type: it is composed of a simple rectangular smoke pipe, which passes through each floor of the house vertically. There is an air inlet connecting the range hood in each floor of the house, and the bottom floor is supplied with air by a make-up air outlet. The principle is that each layer of flue gas is pushed by the range hood to discharge into the flue. Due to the effect of flue gas temperature, the rising buoyancy is generated in the flue, and the flue gas is discharged from the air outlet of the roof.