Interactive three-dimensional visualisation of thermal comfort

For improving feedback about thermal simulation results from engineers to architects, it is desirable to present them in the three-dimensional context of the building. In this paper, we present a system for improved thermal simulation and interactive 3D visualisation of the results. We describe extensions of the physically-based  rendering  system GENESIS-2 towards

• interactive reduction of complex CAD-models for use in building simulation (tesselation/decimation techniques).
• calculation of thermal comfort
• user-friendly interfaces for results exchange and their display within interactive Virtual Environments.

A highlight goes to the fact that the reduced thermal model is exported in STEP language, following a new technical notice of the German Engineers Society (VDI) 6021 "Data Exchange for Thermal Load Simulations". Also, radiation onto walls is simulated by the radiosity method within GENESIS-2. The thermal simulations are then performed by TRNSYS, using an import filter for VDI 6021. The results of this simulation are transferred back to the GENESIS-2 system, where the thermal comfort is calculated according to Fanger’s rule. Finally, the simulation results are visualised in the context of the original CAD-model of the building, enabling the user to interactively walk through the building and examine in real-time the simulated results. Thus, location-dependent   comfort   temperatures   can   be displayed even with a single zone model.