摘要
地铁用制动电阻在非线性动态热应力作用下发生弹塑性大变形。为分析变形机理 ,建立热力耦合的有限元模型 ,其中包括考虑热冲击和变形功影响而建立的非线性瞬态温度场模型 ,考虑几何非线性及材料非线性的位移场模型 ,求得改进应力场的最小二乘法模型。应用有限元程序自动生成系统 (finiteelementprogramgenerator ,FEPG)进行具体的求解计算。最终数值结果表明 ,计算变形与实际变形情况相符 ,验证了分析模型的有效性。根据每一迭代步的温度和位移解回归得到温度与变形的关系曲线 。
Being forced by the nonlinear dynamic thermal stress, slices of the subway's brake resistor generated large elastic plastic deformation. In order to analyze the deformation mechanism, a thermal mechanical coupling model was established by FEM(finite element method). The coupling model included a nonlinear transient temperature field model which was founded by considering the influence of thermal shock and deformation work, a displacement field model which covered geometrical and material nonlinearity, and a stress field model which introduced the least square method to improve the calculation precision. Specific computation was performed by FEPG(finite element program generator) software. Final numerical results display the consistency between computational and actual deformation, which qualifies the analysis model. The regression curve obtained by temperature and displacement solutions of every iterative step provides foundation for taking measures to restrain the deformation.
出处
《机械强度》
CAS
CSCD
北大核心
2004年第5期552-555,共4页
Journal of Mechanical Strength
关键词
地铁
制动电阻
非线性动态热应力
弹塑性大变形
热力耦合
有限元分析
Subway
Brake resistance
Nonlinear dynamic thermal stress
Large elastic plastic deformation
Thermal mechanical couple
Finite element analysis
