English

Simulation techniques have been playing a more and more important role in research and development of reliable and energy efficient building automatic control solutions. Furthermore, simulation is appraised as being viable to judge building automation and control solutions. Therefore, to test and evaluate control strategies, Siemens Building Technologies (SBT) developed a building and HVAC (heating, ventilation and air-conditioning) plant model library.

Weather data in formats required for annual energy simulations are not available at all locations where building designs are being evaluated. Synthetically generated weather data for these sites could be a viable option. This paper reports on the differences in weather and energy prediction results when using synthetically generated data vs. the use of recorded weather data for 50 cities worldwide.

and simulation-based reproduction of performance data from traditional buildings is presented. This approach involves long-term data collection regarding local climate, indoor conditions in the selected building objects, construction methods, building materials, energy systems, ventilation regimes, and occupancy patterns. Subsequently, the collected data is analyzed and interpreted in view of the buildings’ salient design features. Furthermore, a digital performance simulation model of the building is generated and calibrated based on collected indoor climate data.

This study examined the effect of building envelope on thermal comfort. The effects of key energy conservation measures, such as window/wall ratio, transmittance of fenestration glass and shading devices, were studied. The output from EnergyPlus was use to predict their influence on thermal comfort. Standard energy conserving measures proposed by ENVLOAD to reduce indoor thermal discomfort and cooling energy consumption were examined.

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.