YU Zhixiang, YAN Yanjun. Influence on Turbulent Flow Calculation of Wind Flow Around TTU Building by Grid Size Δy in Near-Wall Region[J]. Journal of Civil and Environmental Engineering, 2012, 34(6): 46-51.
DOI:
YU Zhixiang, YAN Yanjun. Influence on Turbulent Flow Calculation of Wind Flow Around TTU Building by Grid Size Δy in Near-Wall Region[J]. Journal of Civil and Environmental Engineering, 2012, 34(6): 46-51. DOI: 10.3969/j.issn.1674-4764.2012.06.008.
Influence on Turbulent Flow Calculation of Wind Flow Around TTU Building by Grid Size Δy in Near-Wall Region
In order to improve the accuracy of simulation in which k-ε EARSM turbulent model was employed
the influence of grids thickness Δy on the turbulent variables in flow field around building was researched. Coupled with real data of Texas Tech University experimental building
Δy as the main parameter was studied in the numerical wind tunnel simulation. Equation of k-ε EARSM and simplified equation of Δy were analyzed and deduced. Quasi-steady State Marching-on-in-time Approximation technology was employed to simulate the average flow in five working conditions
in which y is 0.001m
0.005m
0.01m
0.05m
and 0.1m
respectively. And based on the results
the comparison of characteristic of flow around building
turbulent kinetic energy coefficient
fluctuating pressure coefficient along axis and mean pressure coefficient was conducted. The results indicate that very small Δy will make fluid with high Reynolds number penetrate into near-wall zone
and the calculation stability worsens; on the other side
very large Δy will lower simulated accuracy of main variable results in the turbulent region near the cornice with high Reynolds number. Accordingly
Δy near the wall ranging from 0.01m~0.05m meets the requirements for accuracy and stability
then the experiential formula of Δy upper limit is given.