CFD Simulation Study On Wind-induced Snow Movements Of Folding Reticulated Shell

Folding reticulated shell camping house has advantages of folding conveniently,transporting quickly and so on.Because of these advantages,it is widely used as temporary house to satisfy various needs.When designing the structure,its weight has a small proportion of total load,so the wind load or snow load is usually the main control loads.When the snow drifted by the wind,this kind of structure sensitive to wind and snow will be surrounded by the complex flow and the snow on the surface of the structure will not be uniform.However,current "Load code for the design of building structures"(GB50009-2012)sets the snow distribution on the roof based on the previous design experience,the international standards and foreign data,which only provides snow distribution coefficient of some typical roofs.This can’t be directly applied to the complex shape of folding reticulated shell.At the same time,both the domestic and foreign researches on the snow distribution of roof are imperfect.Therefore,it is of great theoretical significance and applicable value for anti-snow design and development of new products for the in-depth discussion and analysis of wind-induced snow movements in folding reticulated shell.Based on the theories of fluid dynamics and atmospheric boundary layer,this paper uses single-phase coupling assumption of air relative to snow and Mixture multiphase flow model,combines the turbulence model with the CFD numerical simulation technology,develops the computational fluid dynamics software FLUENT’s UDF and UDM interface to program the self-defined boundary conditions for inlet wind profile,snow volume fraction,turbulent kinetic energy and turbulent flow ratio to vary in a functional manner and to automatically calculate and accumulate products in the simulation process,and uses the transient calculation method to simulate wind-induced snow movement around the cube.To verify the feasibility and effectiveness of the calculation method,the simulation results are compared with the results of field observation and wind tunnel tests.On this basis,this paper selects three snow blowing times of the 12 h,24h and 36 h,and five wind speeds of 4.4 m/s,6.7 m/s,9.4 m/s,12.3 m/s and 15.5 m/s,and seven wind direction angles of 0°,15°,30°,45°,60°,75° and 90° as calculation parameters of 65 kinds of cases of the folding reticulated shell with wind-induced snow movement to carry out the numerical calculation,and gets the flow field distribution law of the mixed flow of gas and snow,and calculate the snow distribution coefficient that can be applied to anti-snow design.As a conclusion,the transient calculation method can be used to better simulate the uneven snow distribution under the actual snow-blown time of the folding reticulated shell,there is a large erosion on the windward surface,and there are more depositions on the leeward surface,and the overall erosion is dominated by local deposition,which should be paid attention during the anti-snow design.