Dynamic Responses Analysis Of Wind Turbine Tower Subjected To Environmental Loads

Wind energy is a renewable and clean kind of resource.Rationally making use of wind energy can effectively relieve the energy shortage and environmental pressure that exist in our country nowadays.Compare to the land wind energy ,offshore wind energy has substituent advantage.However, offshore wind turbine tower lies in a fairly complex environment.and it subjects to many style of environmental loads.So it is quite significant that how to make the structure safe.Wind turbine tower may suffer wind force.wave force, ocean current force.and accident seismic force.In the our country's north ocean area,it may suffers ice force. Our design resting on the traditional offshore supporting structure systems as a result of lacking adequate engineering practice and mature standards for reference. Based on the present research status of the supporting structure systems design of wind turbines in our country, the thesis mainly focuses on the following problems by means of theoretical analysis and numerical simulation.(1) Simplified model is established in allusion to the complexity of the offshore wind turbine tower. In order to testify the exactness the simplified model, an exact model is established.Through contrast,it proves that the simplified is reasonable.(2) Through simulating the fluctuating wind velocity time history ,the solution that the structure subject to the wind force is done.(3) As a result of the frozen Bohai sea in winter,a Matlab program is written to simulate the time history of the stochastic ice force.The The result of wind-induced dynamic response of the structure is compared with the result of wind-ice induced response. A conclusion is gotten that the wind and the ice force affect the structure differently.(4) A result of single seismic-induce dynamic response was compared with the result of multi-load dynamic response .In this paper ,a useful conclusion is gotten that the wind turbine tower subjects to the 3 environmental load(considering the existence of the ice load,the ocean wave force is neglected) ,and it can provide some suggestions for the engineer design.