Research On The Fluid-Solid Coupling Effect Of Wind-Induced Vibration Response Of Inflatable Membrane Structure

Inflatable membrane structures are widely used in Civil Engineering nowadays as a new type of special structures. Because of the characteristics of lightweight, large-span and flexible, membrane structures are adaptive to earthquakes but are susceptible to wind-induced dynamic excitation. For wind resisting design of membrane structures, the most predominant feature is the existence of fluid-structure interaction in wind-induced vibration. Currently, theory analysis and related numerical simulation methods of fluid-structure interaction in wind-induced vibration of membrane structures is on the starting phase at home and abroad. Fluid-structure interaction is a key factor of restricting wind-resisting theory development of membrane structures.Firstly, the wind-induced vibration response of hemisphere with height-span ratio of 1/3 is numerical simulated by FLUENT, and is compared with the wind tunnel test. Results show that the mean wind pressure distribution coefficient of the rigid model is basically consistent. Then the initial fluid field of the domain intending to study is numerical simulated after the feasibility of method is verified. This thesis simulates the inflatable membrane structure's coupling characteristics of unidirectional coupling and bilateral coupling under the uniform flow rate, after the inflatable membrane structure was filled with a certain pressure. and external fluid is an incompressible fluid, Partition coupling method is used for this simulation, and the pre-stress of the inflatable membrane structure was got by filling with pre-pressure gas inside. The structure's coupling characteristics in the wind was numerical simulated by the commercial software FLUENT and ABAQUS respectively and the partition coupling between the fluid and the structure is accomplished by use of a method with the on-line transmission between fluid dynamic loads and structure response data based on the commercial software MpCCI.Results show that the inflatable dome structure will have obvious aerodynamic elastic effects in a uniform flow, different frequencies of vortex shedding corresponding to different wind speeds. Resonance phenomenon will happen, when the natural frequency of inflatable membrane structure has certain proportion of the vortex shedding's frequency, the amplitude of the structure will increase severely. Therefore, fluid-structure interaction should be considered when there is fluid both inside and outside of the inflatable membrane structure during the wind-induced vibration response analysis, so as to fully reflect the affection of wind load on the structure's vibration. The research of this thesis has some practical value for wind resisting design of inflatable membrane structures and engineering applications.