English

Ventilation is essential for the health and comfort of building occupants. It is particularly required to dilute and/or remove pollutants emitted by occupants' metabolism and activities. The concentration of metabolic CO2 is well correlated to metabolic odour intensity. Therefore CO2 concentration can be efficiently chosen as an indoor air quality index when occupants are the main source of pollution inside the buildings.

An understanding of airflow patterns in operating rooms is required if the design of air distribution systems in such environments is to be improved and the risk of postoperative infection reduced. To assess a detailed description of contaminant distribution, the airflow patterns and the spread of contaminants in an operating room were analyzed using an experimental model. These experiments were carried out in a test cell, MINIBAT, equipped with an operating table, a medical lamp and a manikin representing the surgeon.

CFD modelling can be used in the design of ventilation systems. However, simplifications in room airflow models may lead to errors and discrepancies between predictions and reality. The aim of this paper is to present the problems and errors connected with the prediction of the air distribution based on CFD codes. The sources of error are pointed out, as well as possibilities for eliminating or reducing them based on program options and experimental identification of the predicted flows. As an example, a real complex room was considered.

The buildings sector is a major energy consumer as it accounts for almost 40% of the EU’s energy requirements and for about 1/3 of the total energy related CO2 emissions. In 2003, the building sector accounted for almost 60% of the total net electricity consumption in the OECD countries. A large share of the electricity consumption accounts for space cooling which has shown an increasing trend in recent years. It is expected that, in future years, the economic growth of many countries and the increased living standards will boost electricity consumption for space cooling.

Traditional naturally ventilated houses are not designed for active thermal control. When natural ventilation is not sufficient for thermal comfort and a fan is unable to restore thermal comfort because the air temperature is higher than the peoples skin temperature, temporary air-conditioning is needed. To maintain indoor thermal comfort and save cooling energy, a new concept of active thermal control for a naturally ventilated house is explored.

Functional availability is used to quantify the probability of a system’s capability both to be in an
operational state and, at the same time, maintain the intended levels of the functions. The purpose of the work described in this paper is to determine if functional availability can be used for the evaluation of performance procurement contracts.

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.