Ventilation and air conditioning systems with independent control of air temperature and pollutant concentration

 In order to solve the problem of air volume mismatch between temperature control and pollutant concentration control in traditional ventilation and air conditioning systems, this research proposes a ventilation and air conditioning system structure and its control method with independent control of air temperature and pollutant concentration. Through the calculation of indoor load and PM2.5 concentration, the PM2.5 concentration levels in typical offices in Beijing, Shanghai and Shenzhen are compared and analysed. The results show that the new system can satisfy the control requirements of indoor temperature and PM2.5 concentration simultaneously. The protection for the indoor environment of the system is outstanding, especially in a moderate climate with heavy air pollution. This research calculates the indoor PM2.5 concentration in a typical office room in Beijing during 2018. At the same indoor temperature, the indoor PM2.5 concentration fully meets the standard with the new system, and exceeds the limit in 10.3% of the year with the traditional system.