合肥工业大学学报(自然科学版)
閤肥工業大學學報(自然科學版)
합비공업대학학보(자연과학판)
JOURNAL OF HEFEI UNIVERSITY OF TECHNOLOGY(NATURAL SCIENCE)
2013年
9期
1076-1081
,共6页
周焕林%江伟%胡豪%牛忠荣
週煥林%江偉%鬍豪%牛忠榮
주환림%강위%호호%우충영
边界条件%反问题%边界元法%截断奇异值分解%L曲线法
邊界條件%反問題%邊界元法%截斷奇異值分解%L麯線法
변계조건%반문제%변계원법%절단기이치분해%L곡선법
boundary condition%inverse problem%boundary element method (BEM )%truncated singu-lar value decomposition(TSVD)%Lcurve method
针对二维各向同性弹性力学Cauchy问题,文章采用线性单元对边界积分方程进行离散,再引入已知的边界条件,得到包含所有待求边界条件信息的线性病态方程组。采用截断奇异值分解正则化技术求解该病态方程组,并使用L曲线法选择最优正则化参数,即奇异值截断位置,从而得到方程组的解。通过数值算例对求得的边界条件数值解与解析解进行比较,并进行误差分析,以表明截断奇异值分解算法的有效性和稳定性。通过减少已知数据中的随机偏差和增加边界单元密度可提高求解的精确度。
針對二維各嚮同性彈性力學Cauchy問題,文章採用線性單元對邊界積分方程進行離散,再引入已知的邊界條件,得到包含所有待求邊界條件信息的線性病態方程組。採用截斷奇異值分解正則化技術求解該病態方程組,併使用L麯線法選擇最優正則化參數,即奇異值截斷位置,從而得到方程組的解。通過數值算例對求得的邊界條件數值解與解析解進行比較,併進行誤差分析,以錶明截斷奇異值分解算法的有效性和穩定性。通過減少已知數據中的隨機偏差和增加邊界單元密度可提高求解的精確度。
침대이유각향동성탄성역학Cauchy문제,문장채용선성단원대변계적분방정진행리산,재인입이지적변계조건,득도포함소유대구변계조건신식적선성병태방정조。채용절단기이치분해정칙화기술구해해병태방정조,병사용L곡선법선택최우정칙화삼수,즉기이치절단위치,종이득도방정조적해。통과수치산례대구득적변계조건수치해여해석해진행비교,병진행오차분석,이표명절단기이치분해산법적유효성화은정성。통과감소이지수거중적수궤편차화증가변계단원밀도가제고구해적정학도。
T he boundary element method(BEM ) is developed to analyze the Cauchy boundary condition inverse problems in 2-D isotropic elasticity .The boundary integral equation is discretized by a set of linear elements ,and after the given boundary conditions have been introduced ,the ill-posed linear system equations with all the unknown boundary conditions can be given .Truncated singular value decomposition(TSVD) technique is applied to solving the equations .L-curve method is proposed to select the regularization parameter ,i .e .the optimal truncation number ,and then the solution of the linear system equations can be obtained .Numerical examples are shown to demonstrate the effective-ness and stability of the TSVD algorithm by the comparison of the obtained numerical solution and an-alytical solution .The regularization errors are also analyzed .The accuracy of the solution can be im-proved by reducing the amount of noise added into the know n data and refining the mesh size .