【作者】 周楠；

【导师】 宋迎东；

【作者基本信息】 南京航空航天大学 ， 航空宇航推进理论与工程， 2010， 硕士

【摘要】 轮盘是航空发动机的断裂关键件,其安全性和可靠性直接影响发动机和飞机的安全性和可靠性。有效评估轮盘材料性能、制造工艺、表面处理方法、结构细节设计以及发展可靠的寿命预测方法,对保证轮盘的安全性和可靠性具有重要意义。传统方法通常是采用等幅疲劳试验开展上述工作。但等幅疲劳试验无法反映轮盘实际使用载荷参量(如载荷次序、小幅循环等)对其疲劳损伤的影响等。因此,发展具有轮盘实际使用载荷特征的标准载荷谱,对上述工作的开展及最终提高轮盘的安全性和可靠性具有重要应用价值。本文主要开展了航空发动机冷端盘(如风扇和前几级压气机轮盘,主要考虑离心载荷)标准载荷谱编制方法的研究,主要工作包括:(1)对国内外标准载荷谱的发展现状进行了文献综述和分析,提出国内发展航空发动机轮盘标准载荷谱的必要性和重要意义。(2)对航空发动机冷端盘标准载荷谱编制方法进行了研究和分析,总结出冷端盘标准载荷谱编制的主要步骤和方法。要发展冷端盘的标准载荷谱,首先需要对航空发动机实测飞行载荷谱进行统计分析,主要内容包括:典型飞行任务剖面的选取和标准化处理、典型飞行任务剖面的任务段划分和载荷分类、确定性载荷的统计分析以及随机性载荷的统计分析。然后基于实测飞行载荷谱的统计分析结果生成冷端盘的标准载荷谱,主要内容包括:确定标准载荷谱长度和典型任务剖面的排列次序、单个任务剖面载荷序列的生成以及最终冷端盘标准载荷谱的生成。(3)基于上述航空发动机冷端盘标准载荷谱编制方法,对国内航空发动机实测飞行载荷谱进行了初步的统计分析,根据统计分析所选取的小载荷去除标准的不同,初步生成了几种不同的国内航空发动机冷端盘标准载荷谱。然后基于国内典型盘所使用的TC4合金的应力疲劳试验数据,对几种标准载荷谱及原始实测谱的疲劳损伤进行了分析,结果表明:小载荷去除标准选为3%最大载荷以内对标准载荷谱的疲劳损伤影响不大,由此生成的标准载荷谱可以较好地表征航空发动机冷端盘的实际使用载荷特征。更多还原

【Abstract】 Aircraft engine disk is of fracture critical part and its safety and reliability is of significance to the safety and reliability of the entire engine and aircraft. Effectively evaluating the performance of disk materials, manufacturing processes, surface treatment methods, structural details of the design and development of reliable life prediction method are important for ensuring the safety and reliability of disks. It is well known that data and models that characterize the fatigue behavior of materials and structures under base-line constant amplitude loading may not be appropriate or sufficient to adequately assess their fatigue performance under irregular variable amplitude loading. From this point of view, fatigue testing should be carried out under a realistic, operational loading pattern. So developing a standardized fatigue test loading sequence for aircraft engine disks is valuable for evaluating the performance of disk materials, manufacturing processes, surface treatment methods, structural details of the design and development of reliable life prediction method.Study in this thesis is focused on the methods for generating a standardized fatigue test loading sequence for aircraft engine cold section discs. Three aspects of research have been accomplished as follow:(1) The development status of the standardized loading sequence is reviewed. It is realized that developing a standardized fatigue test loading sequence in China is of importance and necessary.(2)Through studying and analyzing the generating process for the standardized fatigue test loading sequence, it is concluded that quantitative analysis of aircraft engine’s operational mission profiles is important for generating a standardized fatigue test loading for cold section disks. The analysis procedure mainly comprises: selection and standardization of representative operational mission profiles, statistical analysis with respect to mission type, structure and content. The generating procedure for a standardized loading sequence main comprises: determination of sequence length and mission mix, sequence generation for a mission profiles based on statistical analysis results of representative operational mission profiles, and generation of whole standardized loading spectrum for aircraft engine cold section disks.(3) Based on the generating methods for a standardized loading spectrum, quantitative analysis of aircraft engine’s operational mission profiles in China is carried out. Several sequences have been generated based on different statistical analysis results of representative operational mission profiles with different omitting criterion for small cycles. Then based on the fatigue data of TC4 alloy, the fatigue life is predicted for these different sequences with different maximum stress. It is conclude that omitting small cycles with load range less than 3% of the max load have little influence to the fatigue damage of standardized loading spectrum..更多还原