Numerical Simulation Study On Wind-induced Snow Drifting Of House With Five Ridges And Four Slopes

The house with five ridges and four slopes have been widely used in camping house and civil house in China,because the weight of house is light,it belongs to the structure which is sensitive to wind and snow load.However,there is no relevant regulation of snow load on roof of this type of building in domestic and foreign codes.In snow-resistant design,the load can only be calculated by engineering experience and referring to the approximate shape.At the same time,the existing snow distribution coefficient of roof area in China’s building structural load code has not fully reflected the uneven distribution of snow in the local area of roof.Therefore,it is of theoretical significance and practical value to study the snow cover on the roof of house with five ridges and four slopes.In order to study the distribution law of snow cover on the surface of house with five ridges and four slopes,based on Euler-Euler method,assuming that the air phase is unidirectionally coupled with the snow phase,and considering the erosion and deposition of snow on the wall,the Mixture multiphase flow model of ANSYS Fluent is used to simulate the snow cover distribution around the cube and compare with the measured data to determine the turbulence model,numerical wind tunnel size and fineness.The numerical wind tunnel test was established by setting up the calculation parameters such as the number of meshes,wall conditions and so on.On this basis,nine analysis models with different aspect ratios and different roof gradients are designed for the use functions of houses with five ridges and four slopes.Three wind directions of 0,45 and 90 degrees and the wind speed 5m/s,10m/s,15m/s are selected as analysis parameters.Wind-induced snow drift of roofs under 81 working conditions is simulated numerically.The distribution law of snow in roof area is obtained,and according to the distribution characteristics of snow on roof,the roof is divided into different zones,The snow distribution coefficient suitable for snow resistance design of buildings with five ridges and four slopes is obtained.The results show that with the increase of wind speed,the snow in roof area decreases gradually;the change of wind direction angle will change the characteristics of snow distribution in roof area;the change of length-width ratio has little influence on the snowdistribution in roof area;the increase of roof slope makes the snow in roof area show a decreasing trend;the partition of roof area can describe the snow distribution law in roof area better.