The Spires and roughness elements are most widely used to simulate the atmospheric boundary layer in wind tunnel experiments and have successfully simulated the profiles of wind speed and turbulence intensity for various terrains. With the further development of wind engineering, it is helpful to understand the mechanism of this technique so as to accurately simulate the power spectral density and integral scale of turbulence. Some tests show that spires behave as vortex generators by flow separation on the edges of their windward plate, meanwhile, their linear decrease of blockage with height brings about a corresponding linear wind profile downstream. Roughness elements physically simulate the roughness on earth surface and adjust the profiles of wind speed and turbulence intensity in wind tunnel. However, it is obvious that the profiles of simulated power spectra and integral scales with height are contrary to those in natural atmospheric boundary layer. Based on the knowledge of the mechanism, an improved spire shape has been proposed to simulate the required turbulence profiles for rather large scaled model tests.
|Number of pages||6|
|Journal||Liuti Lixue Shiyan yu Celiang/Experiments and Measurements in Fluid Mechanics|
|Publication status||Published - 1 Jun 2004|
- Atmospheric boundary layer
- Roughness elements
- Turbulence characteristics
- Wind simulation