Numerical Simulation Of Airflow Pattern And Particle Distribution In Personalized Ventilation Room

Airflow pattern is one of the important factors affecting the indoor environment.In the southern part of China,in the high temperature summer,air conditioning and refrigeration are usually turned on indoors,and people spend more than 70% of their working time indoors.Therefore,airflow organization within the research office is particularly important.Mixing ventilation is the most common ventilation method in air conditioning ventilation systems.In some special environments,such as clean rooms,displacement ventilation is usually used.In the mixing ventilation mode,there are poor indoor thermal comfort,low indoor air quality,and large air conditioning energy consumption.The personalized ventilation mode directly supplies air to the local area of the area,so that the air in the vicinity of the human body can be treated,thereby improving the ventilation efficiency around the human body.Therefore,this paper will use numerical simulation method to study the airflow organization,thermal comfort and particle distribution in the personalized ventilation room.First of all,in this same air-conditioned room,the simulation calculation of mixing ventilation,displacement ventilation and personalized ventilation is carried out.The results show that: in the personalized ventilation room,the thermal comfort of the area where the human body is located is high,and the concentration of fine particles in the indoor respiratory area is moderate.The concentration of fine particles in the indoor breathing zone of the replacement ventilation is low,but the indoor thermal comfort is low.The traditional mixing ventilation room has higher thermal comfort,but the indoor fine particle concentration is higher.Personalized ventilation has certain advantages over other ventilation methods.Therefore,it is possible to further carry out research work on individualized ventilation to improve thermal comfort around the human body and control indoor particulate matter.Subsequently,this paper takes the position of the air outlet of the individual ventilation system as the research object,and compares and analyzes the exhaust air outlet on the ceiling,the same side wall with the ventilation opening,the opposite wall and the adjacent wall,and analyzes the personalized ventilation indoor air conditioner.The energy-saving effect and the overall thermal comfort of the room,the study found that: when the exhaust vent is placed at the top of the room,the indoor thermal comfort is higher,and the energy saving is larger.Relatively speaking,the position setting of the exhaust vent has little effect on the concentration distribution of indoor particulate matter.Finally,this paper also studies the concentration distribution of particulate matter in individualized ventilation chambers.According to the source of the particles,the concentration of fine particles of different particle diameters in different areas of the room was compared and analyzed.The study found that: the concentration of small particle size particles in the room is high,and the large particle size is easier to settle;the particles entering the room from the ventilation opening are easier to move to the air outlet than the ground particles resuspended by the ventilation,and the personalized ventilation pair The discharge of particulate matter entering the room from the ventilation port is more efficient.At the same time,the paper also carried out an unsteady numerical simulation of the movement and distribution of indoor particulate matter.The dynamic distribution of indoor particulate matter with time after being affected by ventilation was analyzed within 200 seconds.