Local thermal sensation and comfort study in a field environment chamber served by displacement ventilation system in the tropics

Recently, attention has been given to indoor air quality due to its serious health concerns. Clearly the dispersion of pollutant is directly affected by the airflow patterns. The airflow in indoor environment is the results of a combination of several factors. In the present study, the effects of thermal plume and respiration on the indoor air quality in a ventilated cubicle were investigated using an unsteady computational modeling approach. The person-to-person contaminant transports in a ventilated room with mixing and displacement ventilation systems were studied. The effects of rotational motion of the heated manikins were also analyzed. Simulation results showed that in the cases which rotational motion was included, the human thermal plume and associated particle transport were significantly distorted. The distortion was more noticeable for the displacement ventilation system. Also it was found that the displacement ventilation system lowered the risk of person-to-person transmission in an office space in comparison with the mixing ventilation system. On the other hand the mixing system was shown to be more effective compared to the displacement ventilation in removing the particles and pollutant that entered the room through the inlet air diffuser.

Download Full-text

Numerical Simulation Research on Design of Displacement Ventilation System in Large Painting Workshop

Man-Machine-Environment System Engineering - Lecture Notes in Electrical Engineering ◽

10.1007/978-981-15-6978-4_44 ◽

2020 ◽

pp. 369-377

Author(s):

Bin Yang ◽

Jianwu Chen ◽

Lindong Liu ◽

Yanqiu Sun ◽

Shulin Zhou ◽

...

Keyword(s):

Numerical Simulation ◽

Ventilation System ◽

Displacement Ventilation ◽

Simulation Research ◽

Large Painting

Download Full-text

Modeling the Applicability of a Displacement Ventilation System

International Journal of Manufacturing Materials and Mechanical Engineering ◽

10.4018/ijmmme.2021010105 ◽

2021 ◽

Vol 11 (1) ◽

pp. 63-89

Author(s):

Edgar C. Ambos ◽

Evan Neil V. Ambos ◽

Lanndon A. Ocampo

Keyword(s):

Air Quality ◽

Indoor Air Quality ◽

Indoor Air ◽

Heat Load ◽

Ventilation System ◽

Internal Heat ◽

The Philippines ◽

Airflow Rate ◽

Displacement Ventilation ◽

Tropical Country

Due to its significant role in improving indoor air quality, displacement ventilation system is widely adopted in current literature. This paper proposes a displacement ventilation system for room conditions with ceilings that are relatively low, internal heat load could be high, walls could be sunlit, and occupants doing the low physical activity. These conditions are prevalent in the Philippines, being a tropical country. Input parameters to the design process such as heat load, the height of the ceiling, comfort, and indoor air quality requirements were generated, and the main output parameters are the stratification height and ventilation airflow rate. To demonstrate the proposed displacement ventilation system, four cases were generated. Results show that the ventilation airflow rates obtained from the four cases were greater than the minimum outdoor air requirements for health in conference rooms and large assembly areas which are 17.5 and 3.5 liters/sec*person respectively, for smoking and no smoking rooms.

Download Full-text