Sentry buildings have windows that are often open to facilitate communication between personnel.It also provides the possibility for the intrusion of pollutants such as vehicle exhaust emissions.To prevent the intrusi...Sentry buildings have windows that are often open to facilitate communication between personnel.It also provides the possibility for the intrusion of pollutants such as vehicle exhaust emissions.To prevent the intrusion of outdoor pollutants and create an excellent indoor environment,internal circulation with double-attached ventilation(IC-DAV)and external circulation with double-attached ventilation(EC-DAV)are proposed for such buildings,and the isolation effect of two attached ventilation modes on pollutants is compared with that of natural ventilation.A computational fluid dynamics(CFD)method was used to simulate the transportation process and indoor distribution of outdoor pollutants intruding into sentry buildings from the regular openings under different outdoor wind directions,wind velocities,and states of the doors and ventilation modes.The results indicate that the leeward airflow of the three wind directions caused the largest pollutants to invade the room.The amount of pollutants intrusion increased with increasing wind velocity.When the leeward airflow and the windward airflow blow through the building,opening the door increased the amount of pollutants intruding into the room by 3.34 times and 8.85 times,respectively,compared with closing the door.However,the IC-DAV can isolate 81.7% of the pollutants while the EC-DAV can isolate 99.92% of the pollutants as compared with natural ventilation.Applying double attached ventilation mode in buildings can effectively prevent the intrusion of outdoor pollutants into the room,reduce the harm of outdoor pollutants to the health of indoor personnel,and provide a new idea for buildings to improve the indoor air quality.展开更多
With the emergence of urban sentry boxes and capsule hotels,the development of tiny spaces with the concept of a reasonable minimum occupied space has attracted widespread attention from society.The ventilation mode t...With the emergence of urban sentry boxes and capsule hotels,the development of tiny spaces with the concept of a reasonable minimum occupied space has attracted widespread attention from society.The ventilation mode that fits with the limited geometric characteristics of tiny spaces is worth exploring.Combined with the respective ventilation requirements of two types of tiny spaces,i.e.,sentry box space and tiny sleeping space,this paper proposes two attached ventilation modes.A full-scale experiment cabin was established,and the simulation method was optimized through experimental data.The airflow pattern and distribution performance of the two attached ventilation modes in two types of tiny spaces were studied by the CFD method.The results showed that the airflow attached to the vertical wall could form an air curtain at the opening windows of the sentry box space,but there is a phenomenon of air leakage.The installation of the deflector can improve the integrity of the air curtain,and the best installation angle of the deflector is 60 degrees.The double side-attached ventilation mode in the tiny sleeping space can not only relieve the draught of the occupants(DR<15%),but also firstly deliver fresh air to the occupied zone(expiratory zone MAA<92 s).The research conclusions will add new ideas to the diversity of ventilation modes in tiny spaces.展开更多
基金jointly funded by the National Key Research and Development Program of China(No.2016YFC0700500)the Natural Science Foundation of Shaanxi Province(No.2021JM-361)the Opening Fund of Qinghai Provincial Key Laboratory of Plateau Green Building and Eco-community(No.KLKF-2020-005).
文摘Sentry buildings have windows that are often open to facilitate communication between personnel.It also provides the possibility for the intrusion of pollutants such as vehicle exhaust emissions.To prevent the intrusion of outdoor pollutants and create an excellent indoor environment,internal circulation with double-attached ventilation(IC-DAV)and external circulation with double-attached ventilation(EC-DAV)are proposed for such buildings,and the isolation effect of two attached ventilation modes on pollutants is compared with that of natural ventilation.A computational fluid dynamics(CFD)method was used to simulate the transportation process and indoor distribution of outdoor pollutants intruding into sentry buildings from the regular openings under different outdoor wind directions,wind velocities,and states of the doors and ventilation modes.The results indicate that the leeward airflow of the three wind directions caused the largest pollutants to invade the room.The amount of pollutants intrusion increased with increasing wind velocity.When the leeward airflow and the windward airflow blow through the building,opening the door increased the amount of pollutants intruding into the room by 3.34 times and 8.85 times,respectively,compared with closing the door.However,the IC-DAV can isolate 81.7% of the pollutants while the EC-DAV can isolate 99.92% of the pollutants as compared with natural ventilation.Applying double attached ventilation mode in buildings can effectively prevent the intrusion of outdoor pollutants into the room,reduce the harm of outdoor pollutants to the health of indoor personnel,and provide a new idea for buildings to improve the indoor air quality.
基金This study was jointly funded by the National Natural Science Foundation of China(No.51408477)the Opening Fund of Key Laboratory of Plateau Green Building and Ecological Community in Qinghai Province(No.KLKF-2020-005)the Natural Science Foundation of Education Department of Shaanxi Province(No.21JK0712).
文摘With the emergence of urban sentry boxes and capsule hotels,the development of tiny spaces with the concept of a reasonable minimum occupied space has attracted widespread attention from society.The ventilation mode that fits with the limited geometric characteristics of tiny spaces is worth exploring.Combined with the respective ventilation requirements of two types of tiny spaces,i.e.,sentry box space and tiny sleeping space,this paper proposes two attached ventilation modes.A full-scale experiment cabin was established,and the simulation method was optimized through experimental data.The airflow pattern and distribution performance of the two attached ventilation modes in two types of tiny spaces were studied by the CFD method.The results showed that the airflow attached to the vertical wall could form an air curtain at the opening windows of the sentry box space,but there is a phenomenon of air leakage.The installation of the deflector can improve the integrity of the air curtain,and the best installation angle of the deflector is 60 degrees.The double side-attached ventilation mode in the tiny sleeping space can not only relieve the draught of the occupants(DR<15%),but also firstly deliver fresh air to the occupied zone(expiratory zone MAA<92 s).The research conclusions will add new ideas to the diversity of ventilation modes in tiny spaces.