Paper Conference

Proceedings of SimBuild Conference 2012: 5th conference of IBPSA USA


Simulating Naturally Ventilated Buildings with Detailed CFD-Based Wind Pressure Database

Bing Wang, Timur Dogan, Debashree Pal, Christoph Reinhart
Graduate School of Design, Harvard University, Cambridge, MA
Department of Architecture, Massachusetts Institute of Technology, Cambridge, MA

Abstract: Natural ventilation has long been recognized as a sustainable design strategy to replace or reduce energy associated with fans or active cooling systems in buildings. When it comes to designing a passive system based concept that involves natural ventilation, a major difficulty for design teams is to reliably predict indoor ventilation rates especially in buildings located in a dense urban context. This manuscript proposes a new concept to model ventilation rates and hourly annual indoor temperature distributions using a combination of outside CFD (Computational Fluid Dynamics) calculations and indoor airflow network calculations. In the first step, CFD calculations for eight cardinal wind directions are used to populate a custom database of pressure coefficients for each window in an urban scene. In the second step, hourly wind data and pressure coefficients method have been implemented in Rhinoceros in combination with Phoenics and EnergyPlus. Example results are presented for several typical cases, indicating the improvement of this workflow on simulation results, especially for building with particular shape and urban context.
Pages: 353 - 360