Lynx: A user‐friendly computer application for simulating fatigue growth of planar cracks using FEM

Abstract

People engaged in fracture mechanics education recognise the need to combine theory and effective practice in order to enhance students' skills in this field. Nevertheless, real experiments are not always possible for education purposes because they require too much time, involve specialised equipment and specimen preparation. In these circumstances, numerical simulation is a valid alternative to guarantee the link between theory and practice. In this article, a computer application capable of simulating the fatigue crack growth (FCG) of planar cracks under mode-I cyclic loading is presented. This tool incorporates an extensive range of real significance problems found in the context of FCG. Besides, an intuitive and user-friendly interface was provided in order to improve its functionality and to allow the user to define quickly and easily fundamental input data. Default values are proposed for less experienced users, seeking the minimum effort in numerical model definition. The use of this software in educational context is expected to provide a major insight into FCG phenomenon. ß

3D‐FE automatic procedure to evaluate the fatigue life extension by overloading

“…Fatigue crack growth simulations were performed using the three-dimensional finite-element software LYNX. 48 The geometry and the material modelled were the same described in the previous section. Simulations have considered an initial crack shape with a crack length (a 0 ) equal to 0.5 mm and a straight front and have been finished when the average crack length reached 7.5 mm.…”

“…Fatigue crack growth simulations were performed using the three‐dimensional finite‐element software LYNX . The geometry and the material modelled were the same described in the previous section.…”

Extent of the Surface Region in Notched Middle Cracked Tension Specimens

“…The simulations were carried out using the FCG software Lynx [26]. As referred to above, only eighth of the specimen was modelled.…”

“…Thus, the choice has fallen on the extrapolation method with two points since it combines accuracy and efficiency. Furthermore, this method has been successfully used in diverse situations [25][26][27][28][29][30] and therefore it is well established and well tested.…”

“…The maximum crack advance (∆a max ) is intimately connected with the accuracy of the numerical results in terms of crack shape and fatigue life [26]. In order to ensure good predictions, small values of ∆a max are recommended.…”