Two-dimensional higher-order deformation gradient element for flexible beams with large deformation in a floating frame of reference
摘要
This study proposes a two-dimensional higher-order deformation gradient element based on the floating frame of reference formulation to meet the dynamics control requirements of systems with large deformations/rotations. The proposed model can be regarded as an equivalent element of absolute nodal coordinate formulation, since its derivation process only involves the transformation relationships between coordinate systems without the small deformation assumption. Furthermore, a dynamics model of flexible hub-beam system is derived using the Green-Lagrange strain tensor and the Lagrange’s equation of the second kind, which can precisely describe dynamic behavior undergoing large deformation. Ultimately, several traditional numerical examples, such as a cantilever beam subjected to a vertical tip force, are shown to verify the performance of the proposed model. The results are then compared with existing model methods and ANSYS simulation results. As the results indicate, the computational accuracy of the proposed element is higher than the traditional model. Moreover, the proposed model accurately captures the higher-order deformation characteristics of beam cross sections and effectively address the effects caused by shear locking, including the overestimated bending stiffness and excessively high natural frequency of the system.