Numerical Simulation Of Wind Loads On Membrane Structures

As one of the long-span space structures, membrane structure is used widely in recent years, which is characterized by lightweight, flexibility, small-damping, and belongs to the wind sensitivity structure. Because of the complex figures of membrane structure, wind pressure coefficients on membrane structure surface are commonly determined by wind tunnel testing at home and abroad, however, due to the limited wind tunnel data for various forms of membrane structure, it is insufficient to conduct the regular study. Based on ANSYS-CFX 13.0 softwere platform, research works of numerical simulation in this paper are approached by adopting the Reynolds Averaged Navier-Stokes (RANS) method. Systematic and indepth researchs on wind effects of this kind of structures have important theoretical significance and practical value.The CAARC standard high-rise building model was selected to be research object, and tongji university TJ-2 wind tunnel test was took as reference. Adopting common RANS turbulence model provided by ANSYS-CFX 13.0, the full scale numerical model whose flow boundary conditions was based on measured wind field data was established to study the calculation domain, meshing, boundary conditions, turbulent model and other calculation parameters of numerical similation method. Comparing the numerical simulation results with the measured data of wind tunnel test results, the feasibility and accuracy of numerical simulation method were verified, and the applicability between two turbulence models used in this numerical simulation were discussed.Saddle membrane structure and hexagon umbrella membrane structure were analyzed by adopting finite element softwere ANSYS 13.0, from which the geometry models of membrane structure were extracted. Through importing the model into fluid domain, meshing, establishing fluid calculation model flowing around membrane structure, the numerical simulation of the fluid flowing around membrane structure were realized. In view of the above two basic shape membrane structures, those were, saddle shape and umbrella shape, the influence law of different wind attack angles, rise-span ratios, depth-span ratios on wind pressure distribution of membrane surface were analyzed. The wind pressure distribution rules were summarized, the corresponding wind pressure coefficient distribution on membrane structure surfaces were presented and the corresponding pressure coefficient values for cable-membrane structure designers were provided.