1. Computational Mechanics and Fluid Dynamics, Faculty of Computer Science and Engineering Science , TH Köln/University of Applied Sciences , Claudiusstraße 1 , 50678 Cologne , Germany
2. Chair of Solid Mechanics , Department of Mechanical Engineering , 14312 University of Siegen , Paul-Bonatz-Str. 9–11 , 57068 Siegen , Germany