Probabilistic fatigue life model for medium and low cycle fatigue based on plastic strain energy
-
摘要: 由于材料、尺寸以及载荷等的分散性,涡轮盘疲劳寿命存在较大的分散性。在充分考虑材料加卸载应力、应变及应力比对疲劳寿命影响的基础上,提出了一种适用于中低周疲劳的塑性应变能概率寿命模型。该模型在考虑材料、尺寸和载荷等导致寿命分散的因素的基础上,重点考虑了循环应力应变曲线的分散性,结合根据应力比的二次插值,获得了插值范围内任意应力比下的塑性应变能损伤参量与疲劳寿命的关系。运用所提概率寿命模型结合响应面法与蒙特卡洛法对某涡轮盘螺栓孔模拟试件进行了概率寿命分析。结果显示,模拟试件的计算结果与试验结果的中位寿命仅相差022%,寿命分散系数相差581%,说明本概率寿命模型概率寿命预估精度高。Abstract: The fatigue life of turbine disk may show large scatter duo to the variability of parameters such as material properties, geometrical features, load and some other factors. Taking into full account the influence of factors on the fatigue life, such as stress, strain and stress ratio in the loading and unloading process, a probabilistic fatigue life model based on plastic strain energy was proposed for medium and low cycle fatigue. Besides, the factors commonly used to calculate the scatter of fatigue life, like material property, geometry size and load, the randomness of the cyclic stressstrain curve, were also considered. With the method of quadratic interpolation for stress ratio, the relation of plastic strain energy damage parameter and fatigue life under various stress ratios could be obtained. Using the plastic strain energy probabilistic fatigue life model in conjunction with the response surface method and MonteCarlo method, the probabilistic fatigue life of a simulated bolthole specimen of a turbine disk was analyzed. The results showed that the calculated median fatigue life of the simulated specimen was just 022% less than the median test life, while the fatigue life scatter factor was just 581% less than that of the test result, showing high accuracy of the proposed model for probabilistic fatigue life prediction.
-
[1] APETRE N,ARCARI A,DOWLING N,et al.Probabilistic model of mean stress effects in strainlife fatigue[C]∥1st International Conference on Structure Integrity.Kalpakkam,India:Elsevier,2015:538-545. [2] SANDBERG D,OLSSON M.An investigation of the prediction accuracy for volume based HCF models using scaled geometries and scaled loading[J].International Journal of Fatigue,2016,82(2):317-324. [3] KARLEN K,OLSSON M.A probabilistic model for the entire HCF domain based on equivalent stress:simulations and experiments[J].International Journal of Fatigue,2012,36(1):9-17. [4] 赵永翔,王金诺,高庆.概率循环应变寿命曲线及其估计方法[J].机械设计与研究,2000,16(4):10-12.ZHAO Yongxiang,WANG Jinnuo,GAO Qing.Probabilitybased cyclic strainlife curves and estimation method[J].Machine Design and Research,2000,16(4):10-12.(in Chinese) [5] 唐俊星,陆山.轮盘应变疲劳寿命可靠性分析方法[J].推进技术,2005,26(4):344-347.TANG Junxing,LU Shan.Reliability analysis method for the strain fatigue life of a disk[J].Journal of Propulsion Technology,2005,26(4):344-347.(in Chinese) [6] 陆山,张鸿,唐俊星,等.考虑尺寸效应的轮盘应力疲劳概率寿命分析方法[J].航空动力学报,2011,26(9):2039-2043.
LU Shan,ZHANG Hong,TANG Junxing,et al.Analysis method for the stress fatigue probability life of a disk considering size effect[J].Journal of Aerospace Power,2011,26(9):2039-2043.(in Chinese)[7] 高阳,白广忱.轮盘低循环疲劳寿命可靠性分析方法[J].机械设计与制造,2009(6):60-62.GAO Yang,BAI Guangchen.Reliability analysis method for the low cycle fatigue life of a disk[J].Machinery Design and Manufacture,2009(6):60-62.(in Chinese) [8] 牟园伟,陆山.轮盘低周疲劳概率寿命预估模型[J].推进技术,2012,33(2):288-292.MU Yuanwei,LU Shan.Low cycle fatigue probabilistic life prediction models for fan disk[J].Journal of Propulsion Technology,2012,33(2):288-292.(in Chinese) [9] 高阳,杨昌军,白广忱,等.涡轮盘低循环疲劳可靠性设计方法[J].航空发动机,2011,37(1):4-8.GAO Yang,YANG Changjun,BAI Guangchen,et al.Reliability design of turbine disk low cycle fatigue[J].Aeroengine,2011,37(1):4-8.(in Chinese) [10] 刘康林,黄小平.预测低周疲劳寿命的一种新方法[J].船舶力学,2010,14(1/2):101-105.LIU Kanglin,HUANG Xiaoping.A new method for low cycle fatigue life prediction[J].Journal of Ship Mechanics,2010,14(1/2):101-105.(in Chinese) [11] 中国国家标准化管理委员会.金属材料疲劳试验轴向应变控制方法:GB/T 26077-2010[S].北京:中国质检出版社,2014. [12] 《航空发动机设计用材料数据手册》编委会.航空发动机设计用材料数据手册[M].北京:航空工业出版社,2008. [13] 夏天翔,姚卫星,李旭东,等.工程构件疲劳寿命估算的三维临界域法[J].南京航空航天大学学报,2014,46(3):395-402.XIA Tianxiang,YAO Weixing,LI Xudong,et al.Threedimensional critical zone approach for fatigue life prediction of engineering strcture[J].Journal of Nanjing University of Aeronautics and Astronautics,2014,46(3):395-402.(in Chinese) [14] 杨剑秋,陆山.中长寿命轮盘应力寿命及可靠性分析方法[J].航空动力学报,2007,22(6):991-995.YANG Jiangqiu,LU Shan.Methods for stress based life and its reliability analyses of discs with mediumlong and long life[J].Journal of Aerospace Power,2007,22(6):991-995.(in Chinese) [15] 洪其麟.机械结构可靠性[M].北京:航空工业出版社,1993:103-105. [16] 何水清,王善.结构可靠性分析与设计[M].北京:国防工业出版社,1993:85-90. [17] 高镇同,熊峻江.疲劳可靠性[M].北京:北京航空航天大学出版社,2000:210-214. [18] 马双员,陆山.同应力多危险部位失效相关轮盘疲劳寿命可靠度分析方法[J].航空动力学报,2008,23(11):2016-2020.MA Shuangyuan,LU Shan.Analysis method for the strain fatigue life reliability of a disk concerning failure correlation of critical sites in the same stress level[J].Journal of Aerospace Power,2008,23(11):2016-2020.(in Chinese)
点击查看大图
计量
- 文章访问数: 894
- HTML浏览量: 3
- PDF量: 739
- 被引次数: 0