Analysis Of Wind Load And Wind-induced Vibration Of Shutter Fin Structure

Shutters are widely used in cooling, energy conservation and emissions reduction and ventilation of the high-rise buildings, large factories, key engineering structures, dwellings and large-scale ships. Common shutter is composed of multiple parallel small interval inclined thin walled fin structures. It has the nature of lightweight, small stiffness. The fin structure can produce large deformation and strong vibration with a certain wind speed. Strong wind may cause the plastic deformation and damage. Besides, Strong winds happened frequently in recent year, shutters can be severely damaged if their wind-resistant performance is not good enough, which can consequently result in large economic loss. The broken pieces can also do harm to the people and property in downstream areas. Therefore, disaster evaluation of building structures in extreme weather conditions has become the research focus in the research field of wind engineering all over the world. It is of great practical value to study the wind load on the structure of the thin blade structures and to understand its FSI(Fluid-Structure Interaction)mechanism.However, there are few reports on the research of the shutter, which mainly focus on the aspects of ventilation and ventilation. This paper investigates the wind-induced vibration simulation of the louver structure by using CFD(Computational Fluid Dynamics) and FEM(Finite Element Method), the main research work has the following several aspects:Firstly, single chip and multi-chip model has been established, wind load has been simulated by using the computational fluid dynamics software Fluent. The influence of time step, the quality of the grid and the setting of the calculation on the calculation accuracy is analyzed. The relationship between the wind load and wind attack angle, Reynolds number, the number of fins and the location of the shutter is obtained. The aerodynamic interference effect of multiple parallel fins is defined.Secondly, the structure model of the shutter fin has been built by using the ANSYS software. Through the CFD solution of multiple Reynolds number of wind load on the structure of a unidirectional FSI analysis, the displacement response of the shutter is obtained. The time domain, frequency domain and motion trajectory analysis of the displacement response of single chip and multi-fin shutter are analyzed. The accuracy of CFD simulation is verified by comparing the displacement response value of single and multi-fin parallel shutter with the test values of wind tunnel test.Thirdly, through changing the distance and the angle of the shutter, a variety of conditions is conducted on a multi-blade shutter. From the time domain and frequency domain, the influence of blade pitch and angle on the average value and standard deviation of drag coefficient, lift coefficient and moment coefficient is studied. Several rules of wind load and blade spacing, wind load and blade angle are summarized.Fourthly, the self-compiled Newmark-?program based on C language was embedded into Fluent to achieve a bidirectional FSI simulation of each time step. Based on the dynamic mesh technique provided by Fluent software, the displacement response of the shutter fin is calculated under the condition of considering the nonlinear aerodynamic force. By unidirectional FSI and a bidirectional FSI with the wind tunnel test results of the single and multi-blade shutter, the influence of nonlinear aerodynamic wind-induced loads on the vibration on the shutter is studied. The law of wind load on each blade is studied in the case of nonlinear aerodynamic forces.