Numerical Simulation of Wind Pressure and Wind Vibration Response of Spatial Structure
|School||Shanghai Jiaotong University|
|Keywords||spatial structure fluid-structure interaction wind pressure distribution wind-induced vibration effect|
With the development of computational technology, numerical simulationtechnology, which is based on Computational Fluid Dynamics(CFD), draws more andmore attention in the wind engineering community by its unique merits and promisingprospect. Based upon commercial computational fluid dynamics software, this thesisfocuses on the numerical simulation for wind flow field around structures.The problems about wind engineering, fluid-structure interaction and relatednumerical simulation methods are carefully summarized. The characteristics, such asvelocity Profile, turbulence intensity and turbulence integral scale of the atmosphericboundary layer flow are presented as well. Solutions of the governing dynamicequations of the fluid and structure are presented. The numerical simulation method ofcomputational fluid dynamic can be divided into Direct Numerical Simulation (DNS),Reynolds Average Navier-Stokes (RANS), Large Eddy Simulation (LES), andReynolds Average Navier-Stokes has become a reasonable choice of numerical windresistant research. Turbulence model is introduced to solve the Reynolds AverageNavier-Stokes equation. Several normal turbulence models and the relevant parametersare presented, and a detailed description of the turbulence model and the advantagesand disadvantages of applicable condition is given.A renormalization group k-ε model, the Reynolds Averaged Navier–StokesEquations (RANS) turbulence model, is added in a software Fluent to numericallysimulate the wind flow field around a concave low-rise building with eaves. Then adetailed parametric study is performed for average pressure coefficient and shapefactors of low-rise building with eaves. The parameters include roof pitch, wall height,wall width, wall length and cornices forms. The analysis results show that the roof pressure isn’t affected by the geometry dimensioning of building significantly. Windattack angle, Roof pitch and cornices forms affect both the magnitude and distributionof gable roof pressures. Wind pressures over the roof increase with the increasing ofheight-width ratio. And wind pressures over windward roof decrease while those overleeward roof increase with the increasing of roof pitch. Furthermore, both vertical andhorizontal cornices change greatly the wind pressure distribution around the roof.In the next section, the systemic wind-induced dynamic response numericalsimulations of conical-shaped tension membrane structure is performed using ADINAsoftware，and the effects of some parameters such as inlet velocity, wind direction,rise-span ratio, pre-stress of membrane and the changes of open and close forms of thehat top position are considered. The rules of numerical simulation for wind-induceddynamic responses of the membrane structures are summarized and the wind pressurecoefficients are obtained which can be used in the design of membrane structures.