风荷载的非高斯性对风机结构疲劳损伤的影响

发布时间：2018-04-25 11:13

  本文选题：非高斯风场 + 风场模拟　； 参考：《哈尔滨工业大学学报》2017年12期

【摘要】：为分析非高斯风荷载作用下风机结构的疲劳寿命,在穿越模型基础上,根据Monte Carlo模拟生成某典型风机正常风速条件下,高斯、非高斯硬化和软化3种风场的风速时程,用于分析风场的非高斯性对风机结构疲劳损伤的影响.由叶片的气动模型和多体动力,计算出风机的动力响应,并对响应的时域特性进行分析.基于线性损伤累积和线性裂纹扩展理论,对裂纹形成寿命和裂纹扩展寿命进行详细讨论.结果表明:不同概率特性风场作用下风机动力响应的最大值有所不同,且风机响应的非高斯性较风场的非高斯性减弱;在年平均风速较小地区,风场的非高斯性对风机疲劳寿命影响较小;但随着年平均风速的增大,非高斯性对疲劳寿命的影响显著增大,当年平均风速为7 m/s和9 m/s时,相较于高斯风场,软化过程的裂纹形成寿命减小约10%.因此,在年平均风速较大地区,需要考虑风场的软化特性对风机结构疲劳损伤的影响.
[Abstract]:In order to analyze the fatigue life of fan structure under non- wind load, based on the crossing model, the wind velocity history of a typical fan under normal wind speed conditions was generated according to Monte Carlo simulation. The effect of non-Gao Si of wind field on fatigue damage of fan structure is analyzed. The dynamic response of the fan is calculated from the aerodynamic model of the blade and the multi-body force, and the time domain characteristic of the response is analyzed. Based on the theory of linear damage accumulation and linear crack propagation, the crack forming life and crack propagation life are discussed in detail. The results show that the maximum value of fan dynamic response is different under different probability characteristics of wind field, and the non- property of fan response is weaker than that of wind field, and the annual average wind speed is smaller in the area where the wind speed is small. The non- effect of wind field on the fatigue life of fan is relatively small, but with the increase of annual average wind speed, the influence of non- property on fatigue life increases significantly. When the average wind speed is 7 m / s and 9 m / s, the wind field is different from that of Gao Si wind field. The crack forming life of softening process is reduced by about 10%. Therefore, the influence of the softening characteristics of wind field on the fatigue damage of fan structure should be considered in the area with large annual average wind speed.
【作者单位】： 北京科技大学土木与资源工程学院;北京科技大学强震区轨道交通工程抗震研究北京市国际科技合作基地;
【基金】：国家自然科学基金(51178045) 北京科技大学与台北科技大学专题联合研究计划(TW201601) 高校2016年度引智项目(110000201420160126)
【分类号】：TU312.1
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本文编号：1801073