An approach based on level set method for void identification of continuum structure with time-domain dynamic response

An approach based on the level set method has been developed to identify the position and geometry of voids in continuum structure using time-domain dynamic response. The level set method is employed in the proposed approach to represent the boundary of the voids implicitly. The voids are identified by solving an optimization problem which minimizes an objective function about the displacement error. The boundary of the voids is evolved by updating the level set function. The shape derivative of the objective function for the time-domain dynamic response is derived and used to construct the velocity field. Then, the level set function is updated through the velocity field. The proposed approach has been applied to several numerical examples of void identification in continuum structure. The results indicate that the proposed approach based on the level set method can identify voids effectively and accurately with time-domain dynamic response. Moreover, the effects of measure points, excitation force, noise, void distribution, numerical error, element size and boundary conditions on the approach are studied. Meanwhile, the computational costs of some examples are provided. (C) 2019 Elsevier Inc. All rights reserved.