龙卷风场中沙粒对结构冲击作用的研究

Study on impact action of sand particles in tornado field to the structure

为了研究龙卷风场中沙粒相对结构的作用,首先利用以平均Navier-Stokes方程和RNG k-ε湍流模型为基础的湍流基本方程以及CFD数值方法构建了龙卷风场,并与Rankine涡模型进行对比分析,验证其正确性。随后引入离散相模型,求解了龙卷风场中沙粒运动轨迹,进而探讨了龙卷风场中沙粒对结构的冲击作用。最后,以三门核电常规岛为例,计算发现,当沙粒的体积分数达到0.02%时,顺风向沙粒对结构的冲击等效合力为纯龙卷风作用时的22%,其对结构的作用不可忽视。

In order to study the impact of sand on structure in tornado field, we used the basic turbulence equations and the CFD numerical simulation method based on average Navier-Stokes equations and the RNG k - turbulence model to establish a tornado field, and we made a comparison and analysis of it with Rankine vortex mode to verify its correctness. And then we introduced the discrete phase model to calculate the trajectories of sand in tornado field, and we further explored the impact of sand on the structure. Finally, we took the conventional island of Sanmen Nuclear Power for example, the calculation result shows that, when the sand volume fraction is up to 0. 02% , the equivalent force of downwind sand on the building is 22% of the total wind force in pure tornado field ,which cannot be ignored in structure design.