Erschienen in:IOP Conference Series: Earth and Environmental Science
Sprache:
Nicht zu entscheiden
DOI:
10.1088/1755-1315/356/1/012012
ISSN:
1755-1307;
1755-1315
Entstehung:
Anmerkungen:
Beschreibung:
<jats:title>Abstract</jats:title>
<jats:p>Based on the computational fluid dynamics (CFD) method, the terrain of 2 km near the proposed humanoid landscape bridge in Xiamen is taken as the research object. Firstly, the three-dimensional topographic map is established. Because the selected terrain is relatively flat, the bridge area is adopted in the form of spline curve. The boundary is extended, and the exponential rate of wind speed boundary conditions is applied to the boundary to avoid non-0m/s wind speed from the inflow near wall boundary. The RANS/LES hybrid mode is used to numerically analyze the external flow field of the terrain. The <jats:italic>K - ε - v<jats:sup>2</jats:sup>
</jats:italic> turbulence model of the three equations is used as the RANS part of the RANS/LES hybrid turbulence model. According to the Boussinesq hypothesis and dimension-analysis, the differential form equations of <jats:italic>V</jats:italic>
<jats:sup>2</jats:sup> are rationally simplified, and the algebraic form of the normal stress equation of <jats:italic>V</jats:italic>
<jats:sup>2</jats:sup> and the new turbulent viscosity equation are obtained and written into FLUENT in UDF form. By comparing and analyzing the standard <jats:italic>K -ε</jats:italic> turbulence model and the <jats:italic>SST<jats:sub>κ-ε</jats:sub>
</jats:italic> turbulence model, the wind speed amplification factor and the variation law of wind parameters along the height are studied, and the canyon effect and the reduction effect of the wind field are discussed. The results show that under the same calculation conditions, the mixed turbulence model can accurately reflect the change of airflow in the near-wall wall, and more accurately capture the wind field away from the bridge near the wall.</jats:p>