English

Growing concern about negative effects on the environment and increasing energy prices stress theimportance of energy efficiency. Support processes such as heating, ventilation and air-conditioning(HVAC) use large amounts of energy in the dairy industry. In this paper the energy aspects of the support processes at two large dairies, built at three different points in time, are analyzed and compared with energy use throughout the rest of the company. Significant differences in the use of energy and the resulting indoor climate were found.

Macroscopic methods of building ventilation analysis developed in the past fifty years have proven to be accurate and thus useful for purposes of single- and multi-zone building infiltration, air quality, smoke spread, thermal comfort, and integrated HVAC/building ventilation system analysis. These methods fail, however, to provide the same level of accuracy when applied to the analysis of wind-driven airflow through porous buildings.

The amount of outdoor air ventilation in buildings is one of the most important determinants of indoor air quality, but many critical questions and misunderstandings exist. First, given the importance of ventilation, how well do we know how much outdoor air is even needed in buildings? While research has been done on ventilation and odour perception and on ventilation and symptom prevalence, is it adequate to support the ventilation requirements in our standards and regulations?

The design protocol for wind-driven cross ventilation in buildings should include two processes, namely the determination of required ventilation rate to reduce the room temperature and the prediction of the ventilation rate resulting from the arrangement of openings and wind pressure on those. Computer fluid dynamic techniques (CFD) have the potential to be a useful tool in such calculations but another more practical way is the airflow network model combined with the wind pressure coefficient (Cp) values for buildings with different shapes and surrounding conditions.

Passive cooling by cross-ventilation has been considered to be a key technology for reducing cooling requirements. While various applications have been introduced in both domestic and non-domestic buildings, the strategy of operating windows and air-conditioners to utilize cooling potential has not been well investigated. This paper illustrates how occupants behaviour related to window operation affects the reduction of cooling requirements in domestic buildings.

Human thermal comfort is influenced by psychological as well as physiological factors. Several comfort indices, such as PMV, PPD, TSENS, ET*, DISC, and SET* (see nomenclature) have been developed. These indices attempt to correlate human thermal comfort with environmental conditions. This paper describes the use of a learning algorithm "support vector machine (SVM) learning" for prediction of the thermal comfort indices. The SVM is an artificial intelligent approach that can capture the input/output mapping from the given data.

This paper reviews the literature for evidence of links between ventilation rates in dwellings and moisture related respiratory health with a particular focus on house dust mites (HDM) and fungal growth. There is general consensus that a link exists between ventilation rates in dwellings and respiratory hazards (for example HDM). There is also general consensus of a link between these respiratory hazards and respiratory problems, but it is not clear to what extent hazards cause ill-health.

The paper presents a procedure to estimate natural ventilation flow rates through buildings. The principle is to assume that the flow paths are known and that the whole building is an association of ducts that can be coupled either as series or parallel configurations. The equivalent characteristic airflow vs pressure curve is then established. The main driving force is the pressure difference on faades, expressed via their respective pressure coefficients, together with an appropriate reference wind velocity. A thermal (stack) component may be added to establish the final pressure values.

This paper introduces a ventilation system that combines buried-pipes with multi-purpose windows with the aim of finding an energy efficient, environment-protecting and low-cost way to improve the indoor environment. In this system, buried pipes serve as air-conditioners and multi-purpose windows serve as draught, sound and heat protective devices, in addition to acting as ordinary windows. Further benefits include protection from noise, dust, and insects as well as protection against intruders, thus providing a safe, healthy and comfortable indoor environment.

A building contains a number of large openings, such as doors and staircases. When the temperature of the spaces connected by these openings differs, the difference in density will cause air movements through them.Horizontal air movements through vertical openings in buildings, such as doors and windows are wellinvestigated while studies of air movements through horizontal openings, such as stairwells are less frequent and therefore this work focuses on this case.