Measured air exchange rates at workplace having different types of ventilation.

The aim of the study was to investigate the operation of different types of ventilation in placesconstructed underground and ground level; the effect of ventilation on indoor radon levels wasalso examined. Air exchange rates and radon concentrations were measured in underground(n=73) and ground level (n=64) workplaces. Air exchange rates, designed exhaust ventilationflows, ventilation rates per person and area were sigmficantly higher in underground placesthan places constructed on the ground level.

Macroscopic formulation and solution of ventilation design problems.

This paper will present a general approach that may be used to solve natural ventilation designproblems typically addressed at the preliminary design stage - How wide should windows beopened in a given building for wind-driven cross ventilation on a moderate summer day? Howshould a ventilating monitor be configured to mitigate internal and solar gains on the samesummer day?

Introduction of tools for evaluating domestic ventilation systems.

The IEA project Annex 27, Evaluation and Demonstration of Domestic Ventilation Systems,have come to the stage that simplified tools can be presented in a total scheme. At earlierAIVC conferences some of the tools have been presented in separate papers and still the toolsare under development. In this paper a more general approach of the usage of the tools is to bepresented.The work is based on the joint work of participants from both AIVC countries (CAN,F, NL, S, UK, USA) and non-AIVC countries (I, J).

Increased ventilation airflow rate: night and day cooling of an office building.

This study aims at evaluating the energetical benefits of increased ventilation airflow rate tocool buildings.

IEA Annex 27: comparison of performances of different ventilation systems in similar dwellings.

The main goal of IEA Annex 27 "Evaluation of ventilation systems" is to develop tools toevaluate ventilation systems in an objective way in terms of indoor air quality, energy,comfort, noise, life cycle costs, reliability and other building related parameters.To check the developed tools some measurements in real dwellings are necessary. Thedevelopment of the tools is in its final stage. During the AIVC conference some of these toolswill be presented. The indoor air quality tool is not yet ready.

IEA Annex 27: a simplified tool for the assessment of LCC.

Costs are one of the main decision factors for the selection of domestic ventilation systems.This often leads to a ventilation system that just meets the requirements of buildingregulations at the lowest initial costs. Decision makers are often not aware of the impact of thequality of the ventilation system on life cycle costs, not only for the ventilation system itselfbut also for the building, as a result of complaints or even damage due to a poor functioningventilation system.

IAQ and natural controlled ventilation requirements - performance and standard aspects.

As everybody knows, today the air quality of an indoor environment may have several effectson our health; the beginning of serious breathing pathologies and of some forms of cancer,are with no doubt due to the presence of polluting and extremely noxious agents in the placeswe most frequently use.That's the reason why it is very important that indoor rooms are correctly aired also in ourhomes where, due to several incidental factors, the healthiness of the environment is stillguaranteed by the mere and discretionary operation of users of opening the windows.In considering the growing attenti

Heat pipe heat recovery for passive stack ventilation.

Four types of heat-pipe heat recovery systems were tested for application in passive stackventilation. The effects of fin shape, pipe arrangement and air velocity on the heat recoveryeffectiveness were investigated. The air velocity was found to have a significant effect on theeffectiveness of heat recovery; the effectiveness decreasing with increasing air velocity.The pressure loss coefficient for heat pipe units was also determined.

Hardware and controls for natural ventilation cooling.

This research is part of project NATVENT (TM), a concerted action of nine institutions ofseven European countries under the Joule-3 program. It aims to open the barriers that blocks theuse of natural ventilation systems in office buildings in cold and moderate climate zones.Natural night-time ventilation cooling is a very effective means to remove the heat,accumulated in the building fabrics during office hours. Moreover, it requires no energy at all.Cooling with natural ventilation has it limits; more than 6 air changes per hour have no morecooling effect.

Guidance and tools for night and evaporative cooling in office buildings.

In France, mechanical cooling is increasingly used in office buildings. This situation isrelated to a demand for a better comfort, the increase of the thermal insulation and internalgains, and the changes in the building design.Nevertheless, in many cases, it is possible to achieve a thermally comfortable environmentby passive means - as thermal inertia, and solar protection of the external envelope - and useof low energy techniques as night or evaporative cooling.

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