Numerical simulation of natural ventilation of a bedroom in a warm climate.

This study utilizes the two-chamber model to simulate naturally ventilated airflow through a window opening in a common- type bedroom in Taiwan. Standard kepsilon turbulence model is implemented to account for such a natural convection flow pattern. The driving force in this space is mainly the heat flux generated by occupant's skin. The result shows that under normal operation indoor, carbon dioxide ( indicator air contaminant for IAQ ) is less than 1000 ppm, ASHRAE Standard recommended.

A multi zone ventilation model with contaminant emissions from building materials.

Source/sink models of volatile organic compound (VOC) emissions from building materials are reviewed and a multi-zone ventilation model is developed to predict concentrations of contaminants in rooms. The source model based on the principles of mass transfer and fluid flow presented by Zhang et al. (1995, 1996) is integrated into the multi-zone ventilation model. The characteristics of the parameters related to voc concentration, i.e. Schmidt number, ventilation rate and air velocity at the free stream are investigated by the sensitivity analysis.

Multizone calculations and measurements of air flows in dwellings.

A study of the reliability of systems by considering the ability of different systems to maintain a required air flow rate over time is included in a subtask of IEA Annex 27 "Evaluation and Demonstration of Domestic Ventilation Systems". Measurements and calculations were performed to determine the variation in ventilation rates due to variation in climate and variation in performance of the ventilation system. Dwellings with passive stack, mechanical exhaust and mechanical exhaust-supply ventilation, representative of the Swedish housing stock, were studied.

Comparison of different methods of incorporation of stochastic factors into deterministic models of indoor air quality.

The paper will discuss problems connected with incorporation of stochastic factors into deterministic models of indoor air quality. Three different methods: a quasi dynamic multi-zone modelling with generating of input data time series, multi-zone modelling based on the theory of stochastic differential equations, Monte-Carlo simulation with independent random generating of stochastic parameters, will be shortly presented. Described methods are compared on the base of computer simulation of CO2 concentration in simple two compartment office.

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