Numerical Model Inter-comparison for Wind Flow and Turbulence Around Single-Block Buildings
- 521 Downloads
Wind flow and turbulence within the urban canopy layer can influence the heating and ventilation of buildings, affecting the health and comfort of pedestrians, commuters and building occupants. In addition, the predictive capability of pollutant dispersion models is heavily dependent on wind flow models. For that reason, well-validated microscale models are needed for the simulation of wind fields within built-up urban microenvironments. To address this need, an inter-comparison study of several such models was carried out within the European research network ATREUS. This work was conducted as part of an evaluation study for microscale numerical models, so they could be further implemented to provide reliable wind fields for building energy simulation and pollutant dispersion codes. Four computational fluid dynamics (CFD) models (CHENSI, MIMO, VADIS and FLUENT) were applied to reduced-scale single-block buildings, for which quality-assured and fully documented experimental data were obtained. Simulated wind and turbulence fields around two surface-mounted cubes of different dimensions and wall roughness were compared against experimental data produced in the wind tunnels of the Meteorological Institute of Hamburg University under different inflow and boundary conditions. The models reproduced reasonably well the general flow patterns around the single-block buildings, although over-predictions of the turbulent kinetic energy were observed near stagnation points in the upwind impingement region. Certain discrepancies between the CFD models were also identified and interpreted. Finally, some general recommendations for CFD model evaluation and use in environmental applications are presented.
KeywordsCFD Wind flow Turbulent kinetic energy Building microclimate Pollutant dispersion Model evaluation
This study was carried out within the framework of the ATREUS research network operated under the European Commission Training and Mobility of Researchers Programme (Project Reference: HPRN-CT-2002-00207). We would like to thank all researchers within ATREUS for their support and collaboration. Complete computer support was given to the French team (ECN) by the Scientific Council of Institut de Développement et de Recherche pour l’Informatique Scientifique (IDRIS), Orsay, France. Dr Rex Britter acknowledges the support of the Singapore National Research Foundation through the Singapore-MIT Alliance for Research and Technology (SMART) Center for Environmental Sensing and Modeling (CENSAM).
- 20.Richards, P. J., & Quinn, A. D. (2002). A 6 m cube in an atmospheric boundary layer flow Part 2. Computational solutions. Wind and Structures, 5(2–4), 177–192.Google Scholar
- 29.Sagrado, A. P. G., van Beeck, J., Rambaud, P., & Olivari, D. (2002). Numerical and experimental modelling of pollutant dispersion in a street canyon. Journal of Wind Engineering and Industrial Aerodynamics, 90(4–5), 321–339.Google Scholar
- 32.Hoxey, R. P., Richards, P. J., & Short, J. L. (2002). A 6 m cube in an atmospheric boundary layer flow Part 1. Full-scale and wind-tunnel results. Wind and Structures, 5(2–4), 165–176.Google Scholar
- 36.MIHU (2010). Environmental Wind Tunnel Laboratory Facilities Meteorological Institute. Hamburg University, http://www.mi.uni-hamburg.de/Facilities.311.0.html. Accessed 28 May 2010.
- 44.EIONET (2010). Model documentation system. European Topic Centre on Air and Climate Change. European Environment Information and Observation Network. http://air-climate.eionet.europa.eu/databases/MDS/. Accessed 28 May 2010.
- 47.FLUENT (2005). FLUENT 6.2 version. User's manual. Fluent Inc.Google Scholar
- 49.Britter, R., & Schatzmann, M. (2007). Model evaluation guidance and protocol document. COST Action 732, ISBN 3-00-018312-4.Google Scholar
- 53.Chen, Y. S., & Kim, S. W. (1987). Computation of turbulent flows using an extended k-ε turbulence closure model. NASA CR-179204.Google Scholar
- 60.Franke, J., Hellsten, A., Schlünzen, H., & Carissimo, B. (2007). Best practice guideline for the CFD simulation of flows in the urban environment. COST Action 732, ISBN 3-00-018312-4.Google Scholar