In order to take loading path into account, intermediate configurations are introduced into different forming stages in inverse finite element method(IFEM), multi-step IFEM is presented. Research on multi-step IFEM, a good initial guess is one of key links in the process of solving. So, a kind of reverse mapping method, which is based on sliding constraint surface, has been put forward: Firstly, bending configuration is solved through bending effect of blank and sliding constraint surface is obtained in pseudo minima area optimization algorithm; Then, all nodes in the unfolded final configuration are projected onto the unfolded sliding constraint surface; Thirdly, all projected nodes will be reversely mapped back to sliding constraint surface after these coordinates are calculated in area coordinate. As a result, the corresponding initial guess of intermediate configuration can be obtained. In addition, for the problem of some nodes without projective region in unfolded sliding constraint surface, a solving solution of extending sliding constraint surface is presented. Numerical simulations validate the effectiveness of the algorithm.
ZHANG Xiangkui
,
WANG Feng
,
LIU Weijie
,
DONG Yaya
,
WANG Tianju
. Solving Algorithm of Initial Guess of Intermediate Configuration in Multi-step Inverse Finite Element Method[J]. Journal of Mechanical Engineering, 2015
, 51(24)
: 118
-125
.
DOI: 10.3901/JME.2015.24.118
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