Analysis And Research On The Response Characteristics Of The Wind Load On Portal Crane Under Fluctuating Wind

With the background of economic globalization,the commercial intercourse among countries is getting increasingly closer,which promotes the rapid development of port logistics industry.As the main machinery of the port handling,port crane is developing toward the direction of large scale,high efficiency and specialization,which greatly improves the efficiency of the port loading and unloading operations,however,the carne is also faced with many security risks because of the huge structure.Therefore,it is of great significance to study on wind load of the crane for wind protection design,and it can also reduce the disaster caused by wind load.This thesis takes common portal crane as research object,and uses Transient Structural and CFX module of the ANSYS Workbench to carry out two-way fluid structure coupling analysis on portal crane.Then,the thesis study the response characteristic of the wind load of the portal crane under fluctuating wind and average wind condition,respectively.The results of wind load response of fluctuating wind are compared with the results of average wind condition,and the linear relationship between them is obtained,then propose fluctuating wind load coefficient,which can provide suggestions and reference for the calculation of the wind load and wind protection design of the crane.The main research contents of this thesis are as follows:(1)Analyzing the common power spectrum of fluctuating wind and the simulation method of wind field.Then,using harmony superposition method to simulate standard Davenport spectrum,and obtain time travel curve of fluctuating wind.The reliability of the simulated wind speed curve is verified by comparing the spectral characteristics with the standard spectrum.And it lays the foundation for the establishment of boundary conditions of fluctuating wind field.(2)According to the structure characteristics and stress state of the portal crane,building a simplified model of the portal crane.And analyzing the constraints and typical operating condition.Then,establishing the mathematical model of wind field based on the analysis of the average wind and fluctuating wind environment.(3)Based on the analysis of the wind load response characteristics of the portal crane under the average wind environment,the wind pressure and wind speed of the structure and the surrounding flow field in working status and non-work state are obtained.Then,analyzing the distribution of wind pressure,wind speed and displacement of the portal crane in typical working status and non-work state,respectively.And obtaining the wind load response characteristics of the portal crane under the average wind environment.(4)Analyzing the wind load response characteristics of the portal crane under the fluctuating wind environment.Then,analyzing the time history response of stress,displacement and stability of the portal crane in typical working status and non-work state,respectively,and compared with the results of the average wind load.Based on the comparison,the conclusion that the enhancement effect of the fluctuating wind on the response of the portal crane is obtained.(5)The results of numerical simulation are compared with the results of the theoretical calculation,to verify the reliability of numerical wind tunnel test.The maximum value of the wind load on portal crane of fluctuating wind condition are compared with the wind load on portal crane of average wind condition,and the linear relationship between them is obtained.Then,based on the comparison,fluctuating wind load coefficient is proposed,which can provide suggestions and reference for the calculation of the wind load and wind protection design of the crane.