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This paper reports observations and first experimental results from a field measurement campaign at the neighbourhood/urban scale, which was conducted in July 2010 in Nicosia (Cyprus) under the European Research Project TOPEUM funded by ERA-NET (Urban-Net Call). The ultimate goal of this work is to investigate the influence of urban design and architectural parameters in the resulting urban climate and the resulting energy usage. The field measurement campaign was carried out in the capital city of Cyprus, Nicosia, reflecting a typical Mediterranean city both in relation to buildings architecture and fabrics, street geometry and neighbourhood morphology. The field measurements include meteorological measurements as well as on-ground and aerial thermography, covering a range of spatial scales, from local-street canyon to meso-scale. The measurements record the meteorology, the thermal response of the buildings in the field site area and the resulting local microclimate particularly in the street.

Implementation of diffuse ceiling ventilation (DCV) is slowly gaining momentum and applications in building ventilation have taken off with countries like Denmark, Finland and Netherlands taking the lead in Europe. However, DCV is yet to gain a foothold in Sweden and so not many installations are known, and their performance in relation to Swedish building practice is not yet established. A school in southern Sweden was subsequently renovated and two classrooms were equipped with a sound-absorbent suspended ceiling compatible with DCV. DCV has possible benefits for educational environments including improved thermal comfort as well as lower costs and noise levels. However, it is currently still unknown how supply conditions in the plenum affect the diffusion of air and resulting conditions within the room. To assess airflow characteristics and whether these influence flow conditions in the classroom, we investigated and compared the performance of DCV with two different supply conditions in the plenum. Air speeds and temperature distribution measurements in the plenum and classroom were performed with constant temperature anemometers and thermocouples respectively. The general observation from this study and the system setup herein is that airflow and temperature characteristics in the classroom were independent of the airflow conditions in the plenum. Further investigations in a controlled climate chamber are recommended to investigate and optimise system performance in accordance with Swedish building practice.

The implementation and application of diffused ceiling ventilation (DCV) is gradually gaining momentum, especially in Denmark, Finland, and the Netherlands. In countries such as Sweden, the application is limited despite the favorable conditions for implementation. The current study investigates the performance of DCV and mixing ventilation in a pre-occupancy field study for newly renovated classrooms in Southern Sweden. Two classrooms at the school were installed with diffuse ceiling ventilation while the rest had mixing ventilation. The objective of the study was to compare and evaluate the ventilation performance in terms of indoor environmental quality parameters such as thermal comfort, air quality indexes, airflow, and temperature distribution. Pre-occupancy measurements were performed in two classrooms with similar room characteristics, with one room running under mixing ventilation and the other under DCV. Constant temperature anemometers, thermocouples, and INNOVA thermal comfort were used to measure the indoor air speeds, temperature, and thermal comfort, respectively. Tracer gas measurements, with SF6, were performed to assess air quality. Additionally acoustic measurements were conducted to assess the acoustic benefits of DCV on reducing ventilation noise. The results demonstrate that DCV offers similar indoor environmental conditions to mixing ventilation but has better acoustic performance especially on reducing the ventilation noise. Indoor environmental conditions were very homogeneous under DCV with mixing ventilation showing tendencies for short circuit ventilation. This study demonstrates that DCV has a potential for implementation in Swedish schools with minimal system modification on existing ventilation and air distribution systems.