The paper presents a way of producing an algorithm for the automated construction of mathematical models of air conditioning and ventilating systems with branched air duct networks. The use of mathematical modelling in making aerodynamic calculations of air duct networks allows us to determine the actual value of air flow in network elements. It also permits us to achieve the required air flows effectively in the adjustment of a system.

The purpose of this paper is to improve our understanding of the transient behaviour of airing by window opening. While a few simple models exist to analyse the results of window opening, its transient behaviour is not yet well understood, in its effects on air change rates, air temperature and ventilation efficiency. The paper achieves its purpose in the first place by using a synthesis of numerical modelling activity. Then a critical analysis of the methods of calculation is undertaken, comparing both detailed (CFD) analysis results and simplified or zonal models predictions.

Describes a study based on experimental work carried out in the full-size MiniBat experimental cell, comprising two zones separated by a wall and a door. Experiments were carried out in a steady state, under isothermal and non-isothermal conditions, with a heating system and a manikin. To determine ventilation effectiveness the tracer gas method was used. It was injected into zone 1 and two positions were examined. The study concluded that the heating system favoured the mixing of the air in the cell, which means that the ventilation effectiveness was always close to one.

Aims to study the behaviour of airflow generated by multiple jets and introduced into a room. A finite volumes mathematical model was used in the study, in which the equations were linearised in implicit form and the domain was presented in its discrete elements using the finite volume method. The numerical simulation was performed by creating unstructured computational grids. Findings were compared to experimental data including an extensive series of measurement taken in a model environment setup in a laboratory.

To simulate non-isothermal indoor airflow more quickly and correctly, a turbulence model is performed in STACH-3, the 3-D CFD code developed by Tsinghua University. Validation reveals that it is satisfied for non-isothermal indoor airflow. The air distribution in an actual conference room with VAV system is numerically solved by CFD method, and the conventional jet theory method is used for a comparison of the results. Subsequently an analysis is done of the cold air draught and hot air climbing problems.

The article presents a zonal model called Sim_Zonal which can be used to predict air movement, temperature distribution and comfort characteristics in a room. The model is based on an approximate partitioning of the room, which is divided into a small number of 'cells', usually in the order of 10 to 100, as compared to 10000 or more for typical CFD calculations. Exchanges are calculated between the cells when mass balance and heat balance equations are applied. Empirical laws describe airflow where plumes or jets occur.

Describes an investigation of the possibility of using artificial neural networks to predict air pressure coefficients across openings in a lightweight single-sided naturally ventilated test room. The network was trained using experimental values. A monitoring experiments was carried out on the outside local temperature, wind velocity and direction. Estimates were made of the pressure coefficients at the top and bottom of the openings from the recorded data of air pressures and velocities across the openings with indoor air temperatures.

Describes a global approach to passive design of naturally ventilated buildings situated in the French overseas territories. This approach involves all those involved in the buildings creation process, including architect, owner, building physicists and climate engineers. A validated thermal and airflow building simulation software was used to assess the design and sizing. A reference document was created from the optimal technical specifications, and has been used to build over 800 new pilot homes.

There are important benefits to come from using passive techniques as opposed to artificial cooling. They may not be sufficient to provide thermal comfort throughout the year in wet tropical areas, however. Few experiments have been performed on the thermal performance of buildings using a mixed-running strategy in warm-humid climates. The paper attempts to demonstrate that a possible dual-mode integrated operation can be used for such locations.

The study aimed to identify the behaviour of wind in the type of urban blocks usually found in cities in tropical climates. The results presented here were obtained in colonial type areas. The authors' approach was to establish a relationship between the clusters of buildings and the evidence of overpressures or low-pressure in proximity to the openings of occupied spaces. A prominent physical feature of natural ventilation is the maximal difference of pressure between windward and leeward building facades.