Research Progress of Wind Tunnel Blockage Effects on Building Models

Abstract:

The flow simulated in a wind tunnel is different from that in the free stream of the atmosphere in reality because of the existence of tunnel walls. In certain conditions, large blockage ratios will seriously distort the flow around the building models and the aerodynamics of the building models. Therefore, errors will exist in test results. However, structural wind engineering researchers have paid a little attention to blockage effects. Firstly, this paper briefly introduces the mechanism of blockage effects and concludes the characteristics of the flow and the aerodynamics of buildings under the blockage. Secondly, the main factors which influence the blockage effects are summarized including inflow characteristics, the shape, the number and the arrangement of buildings, etc. Furthermore, the blockage correction methods involved with wind tunnel tests and numerical simulation are reviewed, and the limitation of the blockage ratio is listed from classic works. Finally, some recommendations for future studies are proposed.