Numerical Simulation Of Snow Drifting On Typical Form Of Long-span Roofs

The wind blew over the long-span roof could lead to complex movement of thesnow, resulting in uneven distribution of the snow on long-span roof. In recent years,the collapse accident of long-span roof caused by uneven distribution of snow has beencommon, so it is important to predict the distribution of snow on the long-span roofcorrectly. However, there are few researches about wind-induced snow drifting in Chinaand abroad, a numerical model for simulating the snow drifting on typical long-spanroofs is developed by using the commercial CFD software Fluent14.0. The maincontents in this paper are shown as following:1. The numerical simulation of wind-induced snow drifting. Transport of snowparticles is classified into three processes: creep, saltation and suspension. Consideringthe saltation and suspension, the Mixture multiphase model is used to simulate thewind-induced snow drifting based one-way coupled. At First, the snow drifting around asnow fence is simulated with deferent turbulent models, it found that thek-kl-turbulent model had good suitability and effectiveness. Then the snow driftingaround a cube model is simulated. Compared with field measurements, thecomputational results of snow distribution have good agreement with the experimentaldata.2. The numerical simulation of snow drifting on typical long-span roof. Byusing the CFD numerical methods to simulate the snow drifting on the surface ofseveral typical long-span roof, the distribution of snow on the roof surface is obtainedand the distribution factors are analyzed. Then the simulation result of the flat roof andcylinder roof with the standard load distribution factor in Chinese Code are compared.Based on these, some discussions on snow distribution factor are presented.3. The application on railway station. Based on above method, the CFD methodis used to Harbin west railway station and Daqing west railway station. The contourmaps of snow distribution factor on the surface of roofs under different wind directionsand contour maps of the worst snow distribution factor on the roof partition arepresented to provide a basis for structural design.