薄壁圆盘裂纹的应变分形特征及诊断识别研究  

STRAIN FRACTAL CHARACTERISTICS,DIAGNOSIS AND IDENTIFICATION OF CRACK FOR A THIN DISK

作　　者：徐玉秀[1] 周晓梅[1] 闻邦椿[2] 

机构地区：[1]天津工业大学机械电子学院,天津300160 [2]东北大学机械自动化学院,沈阳110006

出　　处：《振动与冲击》2007年第5期8-10,共3页Journal of Vibration and Shock

基　　金：国家自然科学基金项目(编号:50275024)

摘　　要：运用有限元方法对裂纹圆盘进行动态特性分析,获得振型和应变响应。应用多重分形理论计算和分析裂纹圆盘应变响应的广义维数和敏感维数。把应变广义分形维数、敏感维数作为圆盘裂纹状态的特征量,对圆盘的裂纹诊断与识别进行定性及定量研究。通过计算得到圆盘裂纹的应变广义维数相关系数,用广义维数相关系数法对圆盘裂纹长度进行定量识别。通过对实例的识别分析,考查了裂纹长度的识别精度及广义维数相关系数法对裂纹长度的定量识别的实用性。Dynamic characteristic of a cracked thin disk is analyzed by using finite element method.Its vibration modes and strain responses are obtained.The generalized fractal dimension number and senitive dimension number of the strain responses of the cracked disk are calculated and analyzed by using multi-fractal theory.They as the characteristics of the cracked disk are used for diagnosis and identification of the disk crack.By calculating Correlation coefficients of the generalized fractal dimension number,the length of the disk crack can be quantitatively identified by using the generalized dimension correlation method.Typical examples show that the crack length of a thin disk is identified and close to the actual measured result and that the generalized dimension correlation method is applicable for quatitative identification of disk crack length.

关 键 词：多重分形理论 广义维数相关系数 应变分形特征 裂纹诊断识别 

分 类 号：O322[理学—一般力学与力学基础] TK418[理学—力学]