Finite elements mathematical model of geometric nonlinearity

Abstract

The article considers the construction of a mathematical model for accounting the geometric nonlinearity at finite elements method. The built model takes into account the changes in system stiffness matrix when changing its shape. In quality of an object to compare the results of numerical studies on different models with experimental ones selected is the UAZ automobile spring: symmetric semi-elliptic damper, consisting of fifteen sheets. All numerical studies were performed with two CAD systems: the first one ANSYS, a “heavy” packages representative group, and the SolidWorks, which refers to the average complexity level packages. The results analysis suggests that the traditional nonlinearity model obtained from ANSYS and SolidWorks give approximately the same results at the maximum point of 20,6% differing from the field experiment data. Using the proposed model, the difference is reduced up to 7,95%.