2020 Volume 2020 Pages 20200021
It is essential to deal with contact problems in assembly analyses of mechanical components. However, the usual voxel-based FEM with consideration of contact conditions often exhibits numerical difficulties. In this paper, a practical procedure for 3D frictionless contact in the voxel-based FEM using the EBE-PCG method based on the finite cover method (FCM) is proposed. To assure accuracy in the penalty method for contact conditions, a large penalty parameter, which causes numerical instability and convergence deterioration in iterative linear solvers, is required. In this paper, the Nitsche’s method is applied to contact constraint in the FCM to circumvent such difficulties. Moreover, the ghost penalty is employed to alleviate instability caused by elements with minuscule volume fraction in the FCM. A multi-phased analysis using different voxel size is also proposed to accelerate calculation. To show the effectiveness of the present approach, we calculate basic and practical 3D contact problems.
