Research On Wind-load Numerical Simulation Of Large-span Structure Roof

In recent decades,more and more large-span spatial structures have been used in practical engineering.Such structural shapes are varied and influenced by wind load.Based on the fluent software platform,the wind load distribution law of long-span ellipsoidal roof,columnar roof and crescent-shaped cantilevered roof is calculated and studied by CFD numerical simulation method.On the basis of the existing numerical simulation,the numerical simulation method is expounded in detail.The influence of different height of the first layer of the wall on the surface shape coefficient of the building is studied.Based on the existing wind tunnel test,the wind pressure distribution law of the ellipsoidal roof,the columnar roof and the crescent-shaped cantilevered roof under different roof dimensions and different wind direction angles are systematically studied by using the numerical simulation technology.It is found that the SST k-ω turbulence model can be applied to the reliability of structural wind engineering,and it is found that the value of the wind load factor of the long-span roof has a large error with reference to the Code for Building Structural Load.The influence of grid height on building shape coefficient is very small.The coefficient of body shape of ellipsoidal roof is affected by the ratio of sag to span.As the ratio of sag to span increases from 1/4 to 1/2,the positive pressure area of the windward front extended from 0.085 times to 0.13 times and the maximum positive pressure increased from 0.4 to 0.56.The range of maximum negative pressure distribution is 0.2 times in the middle of the roof,and the maximum negative pressure volume coefficient increases from-0.8 to-1.4.The roof shape coefficient of columnar roof increases from 1/4 to 1/2,and the distribution of positive pressure area increases from 0.04 times to 0.1 times,and the maximum positive pressure volume coefficient increases from 0.4 To 0.7;the maximum negative pressure in the middle of the roof area coefficient increases from-1.0 to-2.0.The wind pressure distribution of roof is affected by the ventilation rate and roof angle,and the roof negative pressure has the largest coefficient of negative pressure with the ventilation rate increasing from 10% to 40% under the 0 ° inclination angle.Value decreased from-2.0 to-1.5.When the ventilation rate was 40%,the roof negative pressure bulk coefficient increased from-1.5 to-1.7 as the roof inclination increased from 0 ° to 10 °.The distribution of wind pressure on roof surface of new stadium in Tianjin University of Traditional Chinese Medicine in 2017 was numerically simulated to find out the distribution of wind pressure under different wind direction angles,and the velocity vector of flow field was analyzed qualitatively.The Rationality of Numerical Simulation Results.Through the above research and analysis,the shape coefficient partition and the value suggestion of each roof shape are given,which provides the reference for the engineering design personnel.