Date：2022-02-12
Comprehensive ventilation can be realized by mechanical ventilation or natural ventilation. O according to different system characteristics, comprehensive ventilation can be divided into comprehensive air supply, comprehensive exhaust, and comprehensive air supply and exhaust. According to different action mechanisms, comprehensive ventilation can be divided into dilution ventilation and displacement ventilation.
Dilution ventilation dilution ventilation, also known as mixed ventilation, is to send air with lower concentration of indoor pollutants to mix with indoor air, so as to reduce the concentration of indoor pollutants and meet the health standard
Displacement ventilation in the displacement ventilation system, the fresh cold air is sent from the bottom of the room at a very low speed (o.03o.59t / s), and the air supply temperature difference is only 24y. The incoming fresh air diffuses like water at the bottom of the whole room due to its high density. The heat convection air flow caused by the heat source makes the room produce vertical temperature Zen, the air flow rises slowly, leaves the working area, pushes the waste heat and pollutants to the top of the room, and then is directly discharged by the exhaust outlet on the ceiling or at the top of the room.
The indoor air flows like a piston, so that the pollutants are discharged from the top of the room with the air flow, and the working area is basically in the incoming air, that is, the pollutant concentration in the working area is about equal to the concentration of the incoming air, which is the main difference between displacement ventilation and traditional dilution comprehensive ventilation. Obviously, the ventilation effect of displacement ventilation is much better than dilution ventilation.
Local ventilation is to make use of local air flow to prevent local places from being polluted by harmful substances and create a good air environment.
Local ventilation system is divided into two categories: local air supply and local exhaust. Local exhaust is to capture and purify the pollutants on site and then discharge them outdoors. Local air supply is to send the treated and qualified air to the local workplace to ensure the air conditions in the local area.
As a technical measure to ensure the air quality of working and living environment and prevent indoor environmental pollution, local ventilation should be given priority.
