IBPSA2007

In reaction to the European Energy Performance of Buildings Directive (EPBD), existing and newly lanced standard developments by CEN (European Committee for Standardization) were harmonized and synchronized, resulting in a set of about 50 standards addressing different aspects of the EPBD and the implementation of an overall building energy performance calculation method. A few of them address simulation issues: An overview of these is given, focusing on one standard covering system related aspects for buildings with cooling, humidification or dehumidification.

Double-skin facade (DSF) is an additional glass skin on the outside wall of the building. In this study a mechanically ventilated and equipped with solar protections (venetian blinds) facade was studied. The airflow inside the facade as well as opening/closing degree of the blinds was controlled in order to increase annual energy performance for both heating and cooling. Numerical simulations for climatic data of Lyon (France) showed good performance of studied DSF compared to a traditional façade.

In an attempt to reduce the high computational efforts for dynamic thermal simulations using Computational Fluid Dynamics (CFD) the authors have recently developed an adaptive freeze-flow method (i.e. freezing of flow equations over variable time periods). This paper documents the work that has been carried out to predict the radiative surface heat transfer in dynamic thermal building processes using CFD. The Monte Carlo and Discrete Transfer radiation models were investigated and results compared with analytical solutions.

Ceiling radiant cooling with its many advantages on thermal comfort or energy reduction, didn’t become a leader in this domain because of the fear of condensation on the chilled surface of the ceiling, especially in hot and humid climates. Using the building simulation code named Trnsys we have been able to simulate the risk of condensation on a cooling ceiling installed in an office room for different France climates.

Taking into account Mediterranean climate particularities for Barcelona, Spain, a whole year study using TAS simulation software was carried out for a Double Skin Façade corporative office building. It is a typical office building with an extended working hours schedule for acclimatization.

Natural ventilation is rapidly becoming a significant part in the design strategy of buildings in situations where electricity is scare or non-existent and saving energy becomes highly important. The aim of present work is to reduce the ceiling temperature by natural ventilation through different opening locations (one window in the front façade and the other window in the rear wall) with sill height ratio of 0.27, 0.36, 0.45, 0.54, and 0.63.

The aim of this case study is to investigate an integrated heating/cooling system performance in central Europe climate conditions. The possibility of a reliable application of radiant low-temperature heating/ high-temperature cooling ceiling system with capillary mats is discussed. ESP-r, an energy performance simulation program, was used for this purpose. Three types of the buildings are taken into account: a residential building, an office building with small offices and an office building with open space offices. Each of them represents a different operating pattern.

The Lyon Confluence project is an actual urban planning operation of Lyon agglomeration. It is part of a global sustainable development process, mixing economic development, social equity and preservation of natural resources.

This paper demonstrates how variations in the estimation of internal gains due to usage affect the cooling demands of speculative office buildings.

The performance of an innovative floor heating application is explored. A two zone building is studied; one zone is frequently overheated due to intensive solar gains while the second zone is essentially unaffected from incident solar radiation. The aim is to explore the possibility to simply extract excess heat from the overheated zone. The idea is to transfer extracted heat through the hydronic floor heating pipe to the second zone; hence, the heat demand for the second zone is decreased. Simulation results yielded a reduced indoor air temperature in the warm zone.