車輛工程外文翻譯--采用非線性有限元方法的車架動(dòng)態(tài)受力分析（原文）

1、1450 KSME International Journal, Vol. 17 No. 10, pp. 1450~ 145Z 2003 Dynamic Stress Analysis of Vehicle Frame Using a Nonlinear Finite Element Method Gyu Ha Kim*, Kyu Zong Cho Deparonent of Mechanical Engineering, Chonna

2、m National University, 300, Yongbong-dong, Buk-gu, Gwangju 500-757, Korea In Bum Chyun Kia Motors Co., Inc 700, Naebang-dong, Seo-gu, Gwangju 502-711, Korea Gi Seob Choi TOP R FAX : -[-82-62-530 1689 Department of Mech

3、anical Engineering, Chonnam National University. 300, Yongbong-dong. Buk-gu, Gwangju 500-757. Korea. (Manuscript Received De- cember 23. 2002: Revised July 19, 2003) vehicle production. Existing dynamic stress an- aly

4、sis for the analysis of vehicle fatigue mainly calculates the dynamic stress history and fatigue after performing dynamic analysis and stress an- alysis with relevant software applications such as DADS and NASTRAN, and t

5、hen superposi- tioning the dynamic load history and stress in- fluence coefficient at each joint. This approach is a complex process, when the flexibility of the parts is taken into account. It is, however, inca- pable o

6、f giving accurate consideration to the contacts between components, the non-linearity of materials, and tire-road surface interactions. This approach also requires the analysts to have an expertise in software applicatio

7、ns of various kinds or an expert in each area to perform the analysis. This requires a great deal of manpower and time. 1452 G.vu Ha Khn, Kyu Zong Cho, In Bum Chyun and Gi Seob Choi bility is [M] ' +S(a, J)+U(al+~g

8、,t-O~=O(lt Here, P and 6) are an acceleration vector and an anglular acceleration vector, respectively, at the flexible body's arbitrary points. And d, a, a are the acceleration vector, the velocity vector and the di

9、splacement vector in regard to flexible body's elastic deformation. In addition, s is a generalized force vector that is dependent on the velocity and U is the internal force vector. ~q is a Jacobian of the restricti

10、on equation, /} is La- grange multiplier vector and Oex is the external force vector. If we ignore the velocity and accel- eration in regard to the flexible body's elastic deformation, we can introduce equation (2) f

11、rom Eq. (1). [M]{/?}+ U(a) ~-(~ff,,l-Qex:O (2) Here, /~ is the rigid body's acceleration vector. The second term is related to the elastic deforma- tion. If we consider the degree of freedom of the finite element mo

12、del, Eq. (2) becomes. U(a) =[h-~{ u }=Q~-[M]{/~ }-~gA (3) Here { u } is a displacement vector, IMP{/~ } is inertia force, and I/)ff, ,} is a joint reaction force is calculated from the dynamic analysis. At a designate

13、d time, this equation could be change a to a static equation, where U(a) is equal to an external force, inertial force, and joint reaction force. Eq. (3), therefore, could be solved by quasi-static finite element analys

14、is in a each stage of dynamic analysis (Kuo and Kelkar, 1995). If we express a general load history as Fe(t), the stress history at a specific point of the body could be introduced as a /brm of linear function which has

15、n load history, as shown in equation (4). a,(t)=f(F~(t)) i=l, ..., ~ (4) When ~ is the unit tbrce vector of load history Fi(l), the equation could be shown as equation (5). F~(t)=C~(t)e~ i=l, ..., n (5) Here, C~(t) i

16、s the magnitude of time varying load. In the quasi-static stress analysis, if a stress field is constant at a specific time, we can say that linear operator f is independent of time. From the superposition principle and

17、quasi-static assump- tion, we can introduce equation (6). ~-~ Point #2 I Point # 1 Fig. 3 Quasi static stress analysis model ,-] “ 1 '4 Ii “4 1 !1 .t W Fig. 4 ~ NDynamic stress history of the point #1 :i i: