CAJ | 학술논문

基于有限元法对裂纹悬臂平板叶片的频率转向和振型转换特性进行了线性和非线性研究。首先使用张开型裂纹模型通过线性模态分析研究了裂纹长度变化引起的频率转向和振型转换问题，使用模态置信因子定量分析了频率转向区内振型的渐变过程。而后考虑裂纹闭合效应，建立了裂纹平板的双线性模型，使用张开型和闭合型模型线性分析结果计算得到双线性频率，其中张开型和闭合型裂纹振型通过模态相关性分析进行匹配。计算了裂纹叶片双线性频率，分析了非线性频率转向特性与线性分析结果的差异。最后使用接触有限元模型瞬态响应扫频计算得到非线性共振频率，对张开型模型和双线性模型在典型弯曲、扭转和面内弯曲模态的共振频率进行了验证。
기우유한원법대렬문현비평판협편적빈솔전향화진형전환특성진행료선성화비선성연구。수선사용장개형렬문모형통과선성모태분석연구료렬문장도변화인기적빈솔전향화진형전환문제，사용모태치신인자정량분석료빈솔전향구내진형적점변과정。이후고필렬문폐합효응，건립료렬문평판적쌍선성모형，사용장개형화폐합형모형선성분석결과계산득도쌍선성빈솔，기중장개형화폐합형렬문진형통과모태상관성분석진행필배。계산료렬문협편쌍선성빈솔，분석료비선성빈솔전향특성여선성분석결과적차이。최후사용접촉유한원모형순태향응소빈계산득도비선성공진빈솔，대장개형모형화쌍선성모형재전형만곡、뉴전화면내만곡모태적공진빈솔진행료험증。
Frequency veering and mode shape interaction of a cracked cantilevered plate blade are simulated using modal analysis and nonlinear analysis in finite element method. Firstly,frequency veering and shape inter?action due to crack length changing are investigated in linear modal analysis using open crack model. The process of shape interaction is quantitatively studied by modal assurance criterion in veering region. Then a bilinear crack model is established by considering crack closure effect. Nonlinear resonant frequencies are calculated using bi?linear crack model. The differences of veering results using linear and nonlinear approaches are discussed. At last,a contact FEM crack model is used to verify resonant frequencies of bending,twisting and in-plane bending modes between open model and bilinear model by forced response sweeping calculation.