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In this paper a new ventilated window with a PCM heat exchanger is proposed. In winter, the heat exchanger works as a solar collector to store heat for pre-heating of the ventilated air. In summer, it works in cooperate with night ventilation to pre-cool the ventilated air. In this work, the prototype of the heat exchanger is built and tested experimentally. The PCM heat capacity measured by differential scanning calorimetry DSC is used to help understand the phase change processes. The PCM temperature at different heights in both melting and freezing processes is measured.

The extremes of arctic climate pose severe challenges on housing ventilation systems, energy consumption and demand for space heating for northern remote community residential buildings. As a part of the overall effort to reduce space heating requirements, dwellings are built air tight to reduce heat losses. However, airtight homes require energy efficient and effective ventilation systems to maintain acceptable indoor air quality and comfort, and to protect the building envelope from moisture damage.

Research shows that, despite compliance with building codes, residential ventilation systems do not deliver the requested air exchanges in the individual rooms. One of the reasons for this can be found in the way the building codes are composed. In general building codes only specify the minimum ventilation capacity that need to be installed in the various rooms. The actual performance of the ventilation system is left to the market.

The AcouReVe Project aimed to improve the knowledge and the quality of acoustic calculation in ventilation ductworks. Such calculations are based on simplified models and the main issue is the input data. For each component of the ductwork, acoustic insertion loss and/or sound generation due to air velocity has to be known. Some components are well described by manufacturers, such as terminal devices, silencers, but others are not known. Sometimes, literature exists and can help to assess the input data, but the values may be out of date or no longer reflect current practices.

This presentation will summarize the last forty-five years of indoor air quality (IAQ) studies, investigations and research from the first energy crisis in the USA in the 1970’s to the latest issues with regards to climate change and its effect on IAQ. The initial occupant complaints about the quality of the air in buildings coincided with changes in infiltration and ventilation in buildings. In particular, the first ASHRAE 62 Standard was issued in 1973, and then substantially changed in the 1981 version.

ADEME is a public organisation to implement public policy in the areas of the environment, energy and sustainable development. ADEME is supervised by the department of ecological transition, the department of higher education and the department of research and innovation. Through management of thesis or export of French innovations for instance, ADEME organises and contributes to the financing of research and innovation to help ecological transition and fight climatic change.  

The French indoor air quality observatory (OQAI) was set up by the French authorities in 2001 with the objective to collect data on indoor pollutants in various indoor environments to be used for public policies. Funded exclusively by public funding, the OQAI is coordinated by the scientific and technical center for building (CSTB) and involved an extensive network of partners across France in charge of the field campaigns and the laboratory analyses. To date, nationwide surveys were carried out in dwellings (2003-2005), schools (2013-2017), and office buildings (2013-2017).

In a sealed building with tight facades, conditions for a good indoor air quality and comfortable conditions must be guaranteed all the time especially for employees. This paper deals with the case of a specific retrofitted building without any openings that immediately shows many difficulties to maintain good indoor air quality in some parts of the occupied volume. An assessment of ductwork and HVAC system performance was first realized, conducted by the SNIA (National Airport Engineering Service).

An accurate temperature gradient calculation is essential for displacement ventilation (DV) system design, since it directly relates to the calculation of supply air flow rate. Several simplified nodal models were developed and implemented in the various building simulation programmes in order to estimate the temperature stratification in rooms with displacement ventilation. However, the most commonly used models do not count the types and locations of the typical heat loads in rooms with displacement ventilation.

The real performances of ventilation systems on site remains a challenge in practice. One of the most common reasons for complaints by the building occupants is the acoustic discomfort. Mechanical ventilation often produces too high levels of noise, mainly coming from the fans. 

Although several good practice recommendations are theoretically known to limit the noise generation by mechanical ventilation systems, the acoustical performance of real ventilation systems on site seems uncontrolled and unexpected.