With the rapid development of large megawatt wind turbines,the operation environment of wind turbine towers(WTTs)has become increasingly complex.In particular,seismic excitation can create a resonance response and cau...With the rapid development of large megawatt wind turbines,the operation environment of wind turbine towers(WTTs)has become increasingly complex.In particular,seismic excitation can create a resonance response and cause excessive vibration of the WTT.To investigate the vibration attenuation performance of the WTT under seismic excitations,a novel passive vibration control device,called a prestressed tuned mass damper(PS-TMD),is presented in this study.First,a mathematical model is established based on structural dynamics under seismic excitation.Then,the mathematical analytical expression of the dynamic coefficient is deduced,and the parameter design method is obtained by system tuning optimization.Next,based on a theoretical analysis and parameter design,the numerical results showed that the PS-TMD was able to effectively mitigate the resonance under the harmonic basal acceleration.Finally,the time-history analysis method is used to verify the effectiveness of the traditional pendulum tuned mass damper(PTMD)and the novel PS-TMD device,and the results indicate that the vibration attenuation performance of the PS-TMD is better than the PTMD.In addition,the PS-TMD avoids the nonlinear effect due to the large oscillation angle,and has the potential to dissipate hysteretic energy under seismic excitation.展开更多
在设计使用年限内,风力发电机组装配式预应力混凝土塔筒的疲劳问题非常突出,尤其在塔筒1/2高度以上区域。国内标准的疲劳验算公式是基于等幅疲劳2×10^(6)次的试验研究结果,而风力发电机组混凝土塔筒的疲劳次数在3×10^(8)以上...在设计使用年限内,风力发电机组装配式预应力混凝土塔筒的疲劳问题非常突出,尤其在塔筒1/2高度以上区域。国内标准的疲劳验算公式是基于等幅疲劳2×10^(6)次的试验研究结果,而风力发电机组混凝土塔筒的疲劳次数在3×10^(8)以上,故国内标准不适用风电机组混凝土塔筒的疲劳验算。而欧标Fib Model Code for Concrete Structures 2010(FIB规范)采用基于S-N曲线的Palmgren-Miner累积损伤方法进行混凝土疲劳验算,可以解决高次数的疲劳问题。介绍了FIB规范中混凝土塔筒常用的Ⅲ级和Ⅳ级设计方法,通过具体案例分析了混凝土塔筒疲劳承载力的影响因素。结果表明:提高混凝土强度等级和加大塔筒壁厚,可以有效提高塔筒的疲劳承载力。可为风力发电机组装配式预应力混凝土塔筒实际设计提供参考。展开更多
基金Fundamental Research Funds for the National Natural Science Foundation of China under Grant No.52078084the Natural Science Foundation of Chongqing (cstc2021jcyj-msxmX0623)+2 种基金the 111 project of the Ministry of Educationthe Bureau of Foreign Experts of China under Grant No.B18062China Postdoctoral Science Foundation under Grant No.2021M690838。
文摘With the rapid development of large megawatt wind turbines,the operation environment of wind turbine towers(WTTs)has become increasingly complex.In particular,seismic excitation can create a resonance response and cause excessive vibration of the WTT.To investigate the vibration attenuation performance of the WTT under seismic excitations,a novel passive vibration control device,called a prestressed tuned mass damper(PS-TMD),is presented in this study.First,a mathematical model is established based on structural dynamics under seismic excitation.Then,the mathematical analytical expression of the dynamic coefficient is deduced,and the parameter design method is obtained by system tuning optimization.Next,based on a theoretical analysis and parameter design,the numerical results showed that the PS-TMD was able to effectively mitigate the resonance under the harmonic basal acceleration.Finally,the time-history analysis method is used to verify the effectiveness of the traditional pendulum tuned mass damper(PTMD)and the novel PS-TMD device,and the results indicate that the vibration attenuation performance of the PS-TMD is better than the PTMD.In addition,the PS-TMD avoids the nonlinear effect due to the large oscillation angle,and has the potential to dissipate hysteretic energy under seismic excitation.
文摘在设计使用年限内,风力发电机组装配式预应力混凝土塔筒的疲劳问题非常突出,尤其在塔筒1/2高度以上区域。国内标准的疲劳验算公式是基于等幅疲劳2×10^(6)次的试验研究结果,而风力发电机组混凝土塔筒的疲劳次数在3×10^(8)以上,故国内标准不适用风电机组混凝土塔筒的疲劳验算。而欧标Fib Model Code for Concrete Structures 2010(FIB规范)采用基于S-N曲线的Palmgren-Miner累积损伤方法进行混凝土疲劳验算,可以解决高次数的疲劳问题。介绍了FIB规范中混凝土塔筒常用的Ⅲ级和Ⅳ级设计方法,通过具体案例分析了混凝土塔筒疲劳承载力的影响因素。结果表明:提高混凝土强度等级和加大塔筒壁厚,可以有效提高塔筒的疲劳承载力。可为风力发电机组装配式预应力混凝土塔筒实际设计提供参考。
