Recent work has begun to consider the potential for using freeze flow techniques in Computational Fluid Dynamics programs for carrying out long term simulations of time dependent flows. This paper describes and tests a new, adaptive control method which automatically adjusts the lengths of the frozen and unfrozen flow periods in the solution procedure, based on current and imminent conditions. The adaptive control method demonstrates improved performance compared with an invariable control method.

An underfloor ventilation system providing three different airflow patterns, a mixing ventilation system, and a displacement ventilation system utilizing a wall-based diffuser were tested in a mock-up of a typical office. The systems were operated under identical conditions. The criteria for evaluation included the distribution of air exhaled by two breathing thermal manikins, pollution emitted from the floor covering, velocity and temperature.

This paper presents some results of the research project "Domestic Violence and Architectural Space", sponsored by several Mexican Governmental Offices and Citizen Organizations. One of the purposes of this project was to find the probable correlation between several physical characteristics of houses and violent behaviour of their inhabitants. In this paper we report the results of the indoor climate exclusively. These results confirm the findings of Givoni and others (2002, 2003, 2004) about the impact of the indoor climate of naturally ventilated buildings on adverse human behaviour.

In the Island city of Mumbai, the Suburban Railway System operates 2500 EMU trains each of 9 or 12 cars and 6.3 millions passengers commute per day. It is considered to be the lifeline of the city. In the morning and evening peak periods loading in each EMU coach is around 500 passengers i.e. 4500 passengers per 9 car train. This is the highest in the world and reflects travel under extremely crowded conditions. During peak periods ventilation, which is practically non- existent, is a serious problem faced by the commuters.

Established methods of computational fluid dynamics (CFD) have been applied to predict the details of airflow, contaminant dispersal and thermal transport within isolated zones, yet zone transport processes do not occur in isolation. They result from and interact with the bulk airflows from the larger whole-building systems in which they are embedded.

This paper presents an assessment of indoor air quality and various ventilation strategies inside a school building located in the south of Portugal. In the first phase, ventilation rate was experimentally evaluated using the tracer gas method. In the second part, different airflow typologies were investigated and, after calculating the air exchange and flow rates for each of them, the evolution of metabolic carbon dioxide inside the spaces was numerically estimated.

The interaction of turbulent plumes is examined in the context of building ventilation flows. Recent models for natural ventilation have been based on simplified treatment of the heat sources in a ventilated enclosure. These models treat buoyancy sources as plumes and assume that they do not interact. To improve the applicability of these models to buildings we examine the effects of plume-plume interaction on the ventilation flow. We present experimental results for the flow in a ventilated enclosure where two plumes in close proximity to each other coalesce to form a single plume.

Desiccant cooling is a potentially environmentally friendly technology which can be used to cool buildings without the use of traditional refrigerants. We have studied the operation of a desiccant cooling system in France. It is used to meet the cooling demand of a training room containing 40 persons. In order to decrease the system primary energy requirement, free cooling techniques are used. Models are implemented in SimSPARK a simulation environment able to solve complex problems. Simulations are run for several French cities.

This paper presents steady-state energy and exergy analyses for dwelling ventilation with and without air-to-air heat recovery, and discusses the relative influence of heat and electricity on the exergy demand by ventilation airflows. Energy and exergy analysis results for De Bilt, NL, are presented in terms of heat and electricity use, on an instantaneous and a daily basis. The amount of electricity input to fans and the heat recovery unit (HRU) is much more significant in terms of exergy than of energy, due to the higher exergy value of electricity.

A model has been proposed for evaluating the discharge coefficient according to the flow angle at an inflow opening for cross-ventilation. This model is based on the fact that the cross-ventilation flow structure in the vicinity of an inflow opening creates dynamic similarity under the condition that the ratio of cross-ventilation driving pressure to dynamic pressure of cross flow at the opening is consistent. It was confirmed from a wind tunnel experiment that the proposed model can be applied almost regardless of wind direction and opening position.