25th AIVC Conference "Ventilation and retrofitting"(Book of Proceedings)

The Book of Proceedings from the 25th AIVC Conference "Ventilation and retrofitting", Prague, Czech Republic, 15-17 September 2004.

25th AIVC Conference - Prague, Czech Republic - 15-17 September 2004

The 25th AIVC Conference, Ventilation and retrofitting, was held in Prague, Czech Republic, 15- 17 September 2004.

Contains 51 papers

The retrofit of existing ventilation and air treatment units : an experimental and methodological approach

Recent studies in Switzerland showed that in large non residential buildings, which can be compared for typology and ventilation needs, the consumption of electricity for mechanical ventilation can vary considerably from case to case. Moreover in such a building it represents a percentage not negligible of the whole consumption of electricity. We had a confirmation of that behaviour with a study we made during 1999-2000 on a set of eighty air treatment units of the Civic Hospital in Lugano (Southern Switzerland).

Hybrid ventilation and user behaviour in summer

Hybrid ventilation is one promising approach to reduce energy consumption in office buildings. On the one hand, a minimum air change rate is supplied to the rooms, even if the windows are closed. On the other hand, the energy demand for ventilation can be reduced if natural forces (wind and buoyancy driven air flow) are used to ventilate the building. The user behaviour has an important but often unknown influence on the thermal building performance and the indoor climate. Thus, an accurate user model should be used in designing hybrid ventilation.

Checking the compliance of residential ventilation systems in France

This paper addresses the issue of the compliance of residential ventilation systems with building regulations. Because the French building code includes requirements on performance as well as on means, the approach adopted by the French government consists in checking both airflow rates and functional measures. This paper gives an overview of the methods used and analyses the results of tests performed on 260 building projects (multi-family buildings and grouped individual houses).

Impact of ventilation systems on indoor air quality and annual energy consumption in school buildings

The paper presents the results of the analysis of the impact of various ventilation systems on indoor air quality and energy consumption, performed for a typical Polish elementary school that was built in 1970s. Simulations were made with the use of two computer codes: CONTAM W and ESP-r. A multizone model of the global capacity of 9464 m3 was performed. The model contained 17 classrooms and 10 additional rooms typical of such buildings.

Indoor air quality in classrooms : field campaign by questionnaires and measurements

A research project aimed at investigating IAQ and thermal, acoustic and visual comfort was carried out in Italian high school and university classrooms. The investigations were performed through field campaigns during regular lesson periods consisting of subjective surveys and measurements. This work focuses in analysing the results from the IAQ investigations at four high schools of Provincia di Torino during the heating period.

Survey on minimum ventilation rate of residential building in fifteen countries

The Minimum Ventilation Rate standard for dwellings is essential not only to provide occupant health and comfort, but also to remove and dilute the dominant pollutants. The purpose of this survey is to clarify and compare the regulations, standards or guidelines of ventilation requirements for residential buildings of various countries. The studies are based on the many literatures and interviews with the specialists in building regulation.

Indoor conditions in ultralightweight structures : a case study

Steel truss structures, covered with a PVC thin sheet of matt light colour, were used in recent time for the construction of three new classrooms in the University of Catania (southern Italy). Although the construction was fast and cheap, the classrooms proved to be uncomfortable in relation to thermal and luminous environment. A first analysis revealed that the drawbacks were caused by the ultra-lightweight of the structure as a whole, resulting in thermal discomfort.

Ventilation systems with longitudinal counterflow spiral recuperations

This paper presents ventilation systems with longitudinal counterflow spiral recuperators. Heat transfer losses in ventilation system can be reduced by increasing the length of the recuperator, but in this case pressure drops increase. These two losses determine exploitation costs. Taking into consideration the results of measurements and calculations the costs for capital expenditure and exploitation of ventilation systems are minimized.

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