One of the common approaches for assessing indoor pollutant level is the continuous sampling. Alternative sampling schemes taking shorter measurements were proposed. For that study a year round indoor CO2 concentration at 17 locations in a typical office in Hong Kong was used to evaluate the probable errors using four sampling schemes :
A - a continuous sampling throughout the measurement
B - 2 sampling periods of 2 equal sessions of the measurement
C - 2 structural sampling periods of the 2 sessions of the measurement
A numerical study of assessment of the performance of a windcatcher using CFD is presented in this paper. A 500 mm square windcatcher system connected to the room has been modeled for different wind speeds in the range of 0.5-6 m/s and four different wind directions. The numerical results agree with the published experimental results of a wind tunnel experiment. The windcatcher system is found to be an efficient way to channel fresh air into the room.
In both airspeed and thermal fields, a scale-model study of an non-isothermal ceiling slot-ventilated enclosure was investigated. Semi-empirical prediction equations have been established. Results have also been compared with previous researches for the validation of the physical behaviour of air-jet. That analysis of airflow performance in a non isothermal condition makes progress in predicting air quality inside the enclosures and it guides the design concepts of ventilation system for an indoor environment.
That study demonstrated the capability of CFD to predict buoyancy-driven displacement natural ventilation flows in a single-storey space connected to an atrium. The CFD simulations were carried out with and without ventilation openings at the bottom of the atrium. The predictions agreed well with the analytical models and the experiments.
The investigation of the effect of the position of doors on performance of the displacement ventilation system was the aim of this paper. A validated CFD simulation was used. It appeared that doors can cause a lateral movement of airflow disrupting the convection effect the displacement ventilation system relies on.
A field measurement and computational energy simulations have been carried out for that study, to examine the effectiveness of commonly used passive climate control methods for naturally ventilated residential buildings in Singapore. Concerning building orientation, faade construction, special roof system and window shading device , their effect on thermal environment and cooling load have been studied. It appears that the most efficient method to reduce the room cooling load is to use the special roof system as thermal buffer.
A theoretical and experimental modelling of a room with low and high level openings is described in this paper with heating distributed at multiple levels. The introduction of an intermediate opening is analyzed too.
In this paper, airflow analysis in an air conditioning room was carried out, in that aim a standard office room was taken up for simulation. temperature and velocity distribution over various virtual planes for different locations of the air conditioner blower were analyzed to achieve the maximum comfort for the occupant. That work can be extended to a more complex air conditioning system like in industries, hospitals, and huge shopping centers.
The aim of this paper is to determine the effects of the use of an electret filter on aerosol penetration. Various factors such as particle size, aerosol charge state, face velocity, and relative humidity were examined to assess their effects on aerosol collection characteristics. The results presented demonstrate that the level of penetration through the electret filter increased with increasing face velocity and relative humidity but was not affected by the temperature and the aerosol charge appeared to exert the greatest influence on aerosol penetration.
The aim of that study was to assess the level of occupational exposure to nitrous oxide in operating rooms. Measurements were carried out during surgical procedures in 35 operating rooms in 10 different Polish hospitals equipped with different systems for ventilation and anaesthetic scavenging. Air was collected in Tedlar bags, and NO2 concentrations were analyzed by adsorption gas chromatography and mass spectrometry.