下降风环境下钝体建筑积雪效应与积雪荷载分布研究

Research on snow accumulations effects and snow loads distribution around a bluff building under katabatic wind

下降风作用会造成建筑表面风荷载增大,当其携带雪颗粒时会造成积雪效应,影响建筑功能正常使用、车辆人员出行乃至结构安全。采用数值仿真(CFD)方法进行了钝体建筑在下降风作用下的积雪分布研究。首先介绍了网格模型和数值方法基础理论,通过建筑外形、网格类型、网格数量、湍流模型和边界条件,搭建钝体建筑积雪分布研究数值模型;然后采用上述气动力分析数值平台进行不同来流下建筑周围的积雪分布数据。研究结果表明,尽管在山体背风面设置建筑模型,下降风夹雪效应依旧十分显著,特别是在风向角变化条件下,积雪范围、积雪高度以及建筑积雪荷载分布受到较大影响,相关研究结果能够为下降风条件下建筑功能和道路规划提供基础数据和依据。

The katabatic wind increases the wind loadings on the building surface.When it carries snow particles,it will cause snow effect,which would hind daily use,road travelling,and even structure safety.Computational fluid dynamics(CFD)method was adopted to study the snow distribution around bluff buildings under the katabatic wind.The mesh model and the basic theory of numerical methods were firstly introduced.Based on the building shape,mesh schematics,grid numbers,turbulence model and boundary conditions,a numerical model for snow distribution around bluff buildings was set up.Then the aerodynamic simulations were carried out to model the snow accumulations around the building under different inflow directions.The results show that even the building model is set on the leeward side of the mountain,the effect of katabatic wind with snow is still very significant,especially under different approaching flows,the distributions of snow accumulation,the height of snow accumulation and the snow loading distribution of the building are greatly affected.The relevant results can provide basic data and guides for building functions and road plannings under katabatic wind.