Simulation of Atmosphere Boundary Layer by Using Wedges and Rough Elements Technique

Abstract

Based on the technique that using wedges and roughness elements to simulate the atmospheric boundary layer, barriers acting as vortex generators were used to effectively increase turbulence intensity on top of wind tunnel. The wind field of atmosphere boundary layer was established by using the devices combination. The mean velocity profile, turbulence intensity profile and power spectra of the simulated wind field were all measured. The changes of mean velocity profile and turbulence intensity profile after adding barriers were discussed. The wedge’ area linear decrease with height decrease brings about a corresponding approximate linear wind speed profile downstream. Roughness elements adjusted the profiles of mean wind speed and turbulence intensity in wind tunnel. The barriers increased turbulence intensity on top of wind tunnel. The test results show that the wind field meets the requirement of low roughness and large turbulence intensity in model test. However, the profiles of simulated turbulence power spectra and integral scales with height are contrary to those in natural atmospheric boundary layer, which is as a result of the figure of wedges.