English

In this paper an approach for pre-calculating building façade incident irradiance levels under a typical, yet computationally complex, external shading device with state-of-the-art ray tracing simulation techniques is presented. The impact of accurate modelling of direct solar, diffuse sky and inter-reflected irradiance components on resulting levels of thermal comfort and energy demand is analysed and recommendations are given for improvement of modelling capabilities.

In  an  existing  integrated  building  design  tool, BSim2002, a 3D building model can be created. The model can be used for thermal simulation, but also for other purposes, e.g. for calculation and visualisa- tion of the solar penetration into a building. The model can be exported to other programs, e.g. for daylight calculations and visualisation.

For the multi-room ventilation calculations, bi- directional flows or counter flows in openings have been rarely taken into consideration and only uni-directional flows have been allowed for the calculation.

Traditionally, the simulation of buildings has focused on operational energy consumption in an attempt to determine the potential  for energy savings. Whilst operational energy of Australian buildings accounts for around 20% of total energy consumption nationally, embodied energy represents 20 to 50 times the annual operational energy of most Australian buildings. Lower values have been shown through a number of studies that have analysed the embodied energy of buildings and their products, however these have now shown to be incomplete in system boundary.

To   provide   additional   validation   data   for   the multizone airflow and contaminant model, CONTAMW, experiments were performed in an occupied 3-story townhouse in Reston, VA. A tracer gas, sulfur hexaflouride (SF6), was manually injected within one room of the house and the concentration of SF6 was measured in each zone. This same process was then recreated in CONTAMW and the resulting predictions were statistically compared to the measured values. A total of 10 experiments were conducted and simulated between May 2000 and June 2001.

Even though simulation is being increasingly used in design of modern buildings, the full potential of simulation is usually not achieved. To improve building and HVAC system performance, designers usually guess different values of design parameters and then redo the simulation without actual knowing if the guessed value will lead to improvement. This is inefficient and labor intensive. In addition, if the number of design parameters being varied exceeds two or three, the designer can be overwhelmed in trying to understand the nonlinear interactions of the parameters.

The  introduction  of  simulation  into  medium-scale building services and engineering firms can provide design teams with access to new information about the performance implications of design decisions. This new information can disrupt "business as usual" and lead to radical changes in how design teams approach projects and in the resulting design. This paper reports on the experiences of consulting firm Rybka Scotland and the Scottish Energy Systems Group in the redevelopment of a historic structure.

In the standard design process of a building, total building simulation using building simulation software is encouraged to be incorporated into the design process as early as possible. However, this paper demonstrates that building simulation can be used as late in the process as the early construction phase of a building project, though usually with increasing cost of building modifications.

The "PV/T-Slate" is a recently developed ventilated photovoltaic slate for integration into roofs or facades. As side effect of the cell cooling the heated air can be used. Therefore it is useful to simulate air volume rate and temperature.

The  design  for  the  new Federal  Building  for  San Francisco includes an office tower that is to be naturally ventilated. The EnergyPlus thermal simulation program was used to evaluate different ventilation strategies for space cooling and rationalize the design of the facade. The strategies include ventilation driven by different combinations of wind, internal stack and external stack. The simulation results indicate that wind-driven ventilation can maintain adequate comfort even during hot periods.